U.S. patent application number 17/826751 was filed with the patent office on 2022-09-08 for flex sensors for measuring real-time valve diameter during procedure.
This patent application is currently assigned to Edwards Lifesciences Corporation. The applicant listed for this patent is Edwards Lifesciences Corporation. Invention is credited to Oren Cohen, Anatoly Dvorsky, Elazar Levi Schwarcz, Natanel Simcha Sirote.
Application Number | 20220280298 17/826751 |
Document ID | / |
Family ID | 1000006389383 |
Filed Date | 2022-09-08 |
United States Patent
Application |
20220280298 |
Kind Code |
A1 |
Schwarcz; Elazar Levi ; et
al. |
September 8, 2022 |
FLEX SENSORS FOR MEASURING REAL-TIME VALVE DIAMETER DURING
PROCEDURE
Abstract
A delivery assembly constituted of: a prosthetic valve
comprising a plurality of intersecting struts, and a delivery
apparatus comprising: a handle; a delivery shaft extending distally
from the handle; and a flex sensing assembly, comprising: at least
one flex sensor coupled to at least one of the plurality of struts;
and a control unit in communication with the at least one flex
sensor, wherein the prosthetic valve is movable between a radially
compressed configuration and a radially expanded configuration, and
wherein, responsive to an output of the at least one flex sensor,
the control unit is configured to generate a signal indicative of a
diameter of the prosthetic valve.
Inventors: |
Schwarcz; Elazar Levi;
(Netanya, IL) ; Cohen; Oren; (Kadima, IL) ;
Dvorsky; Anatoly; (Haifa, IL) ; Sirote; Natanel
Simcha; (Zikhron Ya'akov, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Edwards Lifesciences Corporation |
Irvine |
CA |
US |
|
|
Assignee: |
Edwards Lifesciences
Corporation
Irvine
CA
|
Family ID: |
1000006389383 |
Appl. No.: |
17/826751 |
Filed: |
May 27, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/US2020/062989 |
Dec 3, 2020 |
|
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17826751 |
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62945010 |
Dec 6, 2019 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2/2418 20130101;
A61F 2250/001 20130101; A61F 2/9517 20200501; A61F 2/2433 20130101;
A61F 2250/0096 20130101; A61F 2/2496 20130101 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. A delivery assembly, comprising: a prosthetic valve movable
between a radially compressed configuration and a radially expanded
configuration, the prosthetic valve comprising a plurality of
intersecting struts and at least one coupling member; a delivery
apparatus comprising: a handle; a sensor shaft extending distally
from the handle; at least one flex sensor configured to be
removably coupled to at least one of the plurality of struts; a
control unit in communication with the at least one flex sensor and
configured to generate a signal indicative of a diameter of the
prosthetic valve based at least in part on an output of the at
least one flex sensor; at least one communication channel
configured to detachably couple with the at least one flex sensor
and allow communication between the at least one flex sensor and
the control unit; wherein the at least one coupling member is
coupled to a first strut of the plurality of intersecting struts;
and wherein the at least one flex sensor is configured to be
coupled to the at least one coupling member and slide within the at
least one coupling member relative to the first strut during valve
expansion or compression.
2. The delivery assembly of claim 1, wherein the delivery apparatus
further comprises: a control unit in communication with the at
least one flex sensor; and at least one communication channel
detachably coupled to the at least one flex sensor and configured
to allow communication between the at least one flex sensor and the
control unit, wherein the control unit is configured to generate a
signal indicative of a diameter of the prosthetic valve based at
least in part on an output of the at least one flex sensor.
3. The delivery assembly of claim 2, wherein the at least one
communication channel is axially movable within the sensor
shaft.
4. The delivery assembly of claim 1, wherein the at least one flex
sensor comprises a non-bending portion and a bending portion
configured to flex relative to the non-bending portion.
5. The delivery assembly of claim 4, wherein the bending portion of
the at least one flex sensor is configured to bend about a distal
end of the sensor shaft.
6. The delivery assembly of claim 4, wherein the non-bending
portion of the at least one flex sensor is coupled to at least one
actuator assembly of the prosthetic valve.
7. The delivery assembly of claim 1, wherein the prosthetic valve
further comprises at least one actuator assembly, wherein the
delivery apparatus further comprises an actuation member releasably
coupled to the at least one actuator assembly, and wherein the
actuation member is configured to move the prosthetic valve between
the radially compressed state and the radially expanded state.
8. The delivery assembly of claim 1, wherein the at least one
coupling member comprises at least one of: a suture, a band, a
tube, or a sleeve.
9. The delivery assembly of claim 1, wherein the at least one flex
sensor is slidable relative to the at least one coupling member
upon application of a force exceeding the frictional force applied
by the at least one coupling member on the at least one flex
sensor.
10. The delivery assembly of claim 1, further comprising: an
inflatable balloon positioned within the prosthetic valve; a
reservoir containing a predetermined volume of inflation fluid; a
pump in fluid communication with the reservoir; and a fluid flow
channel, a distal end of the fluid flow channel in fluid
communication with an opening of the inflatable balloon and a
proximal end of the fluid flow channel in fluid communication with
the pump, wherein inflation of the inflatable balloon is configured
to cause movement of the prosthetic valve between the radially
compressed configuration and the radially expanded configuration;
and wherein the pump is configured to generate flow of the
inflation fluid into the inflatable balloon via the fluid flow
channel.
11. The delivery assembly of claim 10, wherein the flow of the
inflation fluid is based at least in part the signal indicative of
the diameter of the prosthetic valve.
12. A delivery assembly, comprising: a prosthetic valve movable
between a radially compressed configuration and a radially expanded
configuration, the prosthetic valve comprising: a plurality of
intersecting struts; a sensor housing coupled to at least one of
the plurality of struts; and at least one flex sensor coupled to
the sensor housing, the at least one flex sensor configured to flex
during valve expansion or compression; and a delivery apparatus
comprising: a handle; a detachable shaft extending distally from
the handle; and at least one communication channel configured to
detachably couple with the at least one flex sensor and allow
communication between the at least one flex sensor and a control
unit, wherein the detachable shaft is configured to detachably
couple to the sensor housing and isolate the at least one
communication channel from ambient flow.
13. The delivery assembly of claim 11, wherein the at least one
communication channel extends through the detachable shaft and is
axially movable within the detachable shaft.
14. The delivery assembly of claim 11, wherein the at least one
communication channel is detachable from the at least one flex
sensor upon application of a pull force on the at least one
communication channel greater than a predetermined threshold.
15. The delivery assembly of claim 11, wherein the sensor housing
comprises a proximal threaded end, wherein the detachable shaft
comprises a distal threaded end, wherein the distal threaded end of
the detachable shaft is configured to engage with the proximal
threaded end of the sensor housing.
16. The delivery assembly of claim 11, wherein the at least one
flex sensor is an optic flex sensor configured to generate an optic
signal, wherein the at least one communication channel is an optic
conductor.
17. The delivery assembly of claim 11, further comprising: an
inflatable balloon positioned within the prosthetic valve; a
reservoir containing a predetermined volume of inflation fluid; a
pump in fluid communication with the reservoir; and a fluid flow
channel, a distal end of the fluid flow channel in fluid
communication with an opening of the inflatable balloon and a
proximal end of the fluid flow channel in fluid communication with
the pump, wherein inflation of the inflatable balloon is configured
to cause movement of the prosthetic valve between the radially
compressed configuration and the radially expanded configuration;
and wherein the pump is configured to generate flow of the
inflation fluid into the inflatable balloon via the fluid flow
channel.
18. The delivery assembly of claim 17, wherein the delivery
apparatus comprises a control unit configured to generate a signal
indicative of a diameter of the prosthetic valve based at least in
part on an output of the at least one flex sensor, and wherein the
flow of the inflation fluid is based at least in part the signal
indicative of the diameter of the prosthetic valve.
19. A method of delivering a prosthetic valve, the method
comprising: providing a prosthetic valve comprising a plurality of
intersecting struts and at least one flex sensor couple to at least
one of the plurality of intersecting struts; providing a delivery
apparatus comprising a handle, an actuator, and at least one
communication channel; coupling the at least one communication
channel with the at least one flex sensor; coupling the actuator to
an actuation assembly of the prosthetic valve; delivering the
prosthetic valve to a predetermined anatomical location; actuating,
via the actuator, the actuation assembly of the prosthetic valve to
cause the prosthetic valve to move between a radially compressed
configuration and a radially expanded configuration; determining an
estimated diameter of the prosthetic valve based at least in part
on a signal generated by the at least one flex sensor, wherein the
signal is indicative of an amount of bend experienced by the at
least one flex sensor; detaching the at least one communication
channel from the at least one flex sensor; detaching the actuator
from the actuation assembly of the prosthetic valve.
20. The method of claim 19, wherein the detaching the at least one
communication channel from the at least one flex sensor comprises:
detaching a detachable shaft of the delivery apparatus from a
sensor housing of the at least one sensor flex sensor, wherein the
at least one communication channel extends axially within the
detachable shaft, and wherein the at least one sensor flex sensor
is housed within the sensor housing.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of a PCT Patent
Application No. PCT/US2020/062989, entitled "FLEX SENSORS FOR
MEASURING REAL-TIME VALVE DIAMETER DURING PROCEDURE," filed Dec. 3,
2020, which claims the benefit of U.S. Provisional Application No.
62/945,010, entitled "FLEX SENSORS FOR MEASURING REAL-TIME VALVE
DIAMETER DURING PROCEDURE," filed Dec. 6, 2019, all of which are
incorporated by reference herein in their entirety.
FIELD
[0002] The present invention relates to devices and methods for
measuring prosthetic valve expansion diameter, and in particular,
for devices equipped with at least one flex sensor configured to
provide real-time estimate of prosthetic valve expansion
diameter.
BACKGROUND
[0003] Native heart valves, such as the aortic, pulmonary and
mitral valves, function to assure adequate directional flow from
and to the heart, and between the heart's chambers, to supply blood
to the whole cardiovascular system. Various valvular diseases can
render the valves ineffective and require replacement with
artificial valves. Surgical procedures can be performed to repair
or replace a heart valve. Surgeries are prone to an abundance of
clinical complications, hence alternative less invasive techniques
of delivering a prosthetic heart valve over a catheter and
implanting it over the native malfunctioning valve, have been
developed over the years.
[0004] Mechanically expandable valves are a category of prosthetic
valves that rely on a mechanical actuation mechanism for expansion.
The actuation mechanism usually includes a plurality of
actuation/locking assemblies, releasably connected to respective
actuation members of the valve delivery system, controlled via the
handle for actuating the assemblies to expand the valve to a
desired diameter. The assemblies may optionally lock the valve's
position to prevent undesired recompression thereof, and
disconnection of the delivery system's actuation member from the
valve actuation/locking assemblies, to enable retrieval thereof
once the valve is properly positioned at the desired site of
implantation.
[0005] When implanting a prosthetic valve, such as a mechanically
expandable valve, it is desirable to expand the valve to a maximum
size allowed by the patient's anatomical considerations, in order
to avoid paravalvular leakage or other unfavorable hemodynamic
phenomena across the valve that may be associated with a mismatch
between the valve's expansion diameter and the surrounding tissue,
while mitigating the risk of annular rupture that may result from
over-expansion. To ensure optimal implantation size, the diameter
of the prosthetic valve should be monitored in real-time during the
implantation procedure.
SUMMARY
[0006] The present disclosure is directed toward devices,
assemblies and methods for monitoring radial expansion of a
prosthetic valve during prosthetic valve implantation procedures.
Real-time measurement of the expansion diameter ensures proper
implantation of the prosthetic valve within a designated site of
implantation, such as the site of malfunctioning native valve.
[0007] According to one aspect of the invention, a delivery
assembly is provided the delivery assembly comprising: a prosthetic
valve comprising a plurality of intersecting struts, and a delivery
apparatus comprising: a handle; a delivery shaft extending distally
from the handle; and a flex sensing assembly, comprising: at least
one flex sensor coupled to at least one of the plurality of struts;
and a control unit in communication with the at least one flex
sensor, wherein the prosthetic valve is movable between a radially
compressed configuration and a radially expanded configuration, and
wherein, responsive to an output of the at least one flex sensor,
the control unit is configured to generate a signal indicative of a
diameter of the prosthetic valve.
[0008] According to some embodiment, the at least one flex sensor
comprises a non-bending portion and a bending portion configured to
flex relative to the non-bending portion.
[0009] According to some embodiments, the prosthetic valve further
comprises at least one actuator assembly, wherein the delivery
apparatus further comprises an actuation member releasably coupled
to the at least one actuator assembly, and wherein the prosthetic
valve is expandable from the radially compressed state to the
radially expanded state upon actuating the at least one actuator
assembly by the at least one actuation member.
[0010] According to some embodiments, the prosthetic valve further
comprises at least one actuator assembly, wherein the delivery
apparatus further comprises an actuation member releasably coupled
to the at least one actuator assembly, wherein the prosthetic valve
is expandable from the radially compressed state to the radially
expanded state upon actuating the at least one actuator assembly by
the at least one actuation member, and wherein the non-bending
portion of the at least one flex sensor is coupled to the at least
one actuator assembly.
[0011] According to some embodiments, the delivery assembly further
comprises at least one communication channel, a first end of the at
least one communication channel coupled to the at least one flex
sensor and a second end of the at least one communication channel
extending towards the handle, wherein the at least one
communication channel is retractable from the prosthetic valve.
[0012] According to some embodiments, the flex sensing assembly
further comprises a sensor shaft extending distally from the
handle, and wherein at least a portion of the at least one
communication channel extends through the sensor shaft.
[0013] According to some embodiments, the delivery assembly further
comprises: at least one sensor housing attached to a strut; and at
least one detachable shaft extending distally from the handle, and
detachably coupled to the sensor housing, wherein the at least one
flex sensor is locally attached to the at least one sensor housing;
wherein at least a portion of the at least one communication
channel extends through the at least one detachable shaft; wherein
the communication channel is detachably coupled to the at least one
flex sensor; wherein the detachable shaft is configured isolate the
at least one communication channel from ambient flow, when the
detachable shaft is coupled to the sensor housing; and wherein the
at least one communication channel is axially movable relative to
the at least one detachable shaft, when the at least one
communication channel is detached from the at least one sensor.
[0014] According to some embodiments, the at least one
communication channel is detachable from the at least one flex
sensor upon application of a pull force on the at least one
communication channel, and wherein the magnitude of the pull force
is higher than a predetermined threshold magnitude.
[0015] According to some embodiments, the sensor housing comprises
a sensor housing proximal threaded end, and wherein the detachable
shaft comprises a detachable shaft distal threaded end, configured
to engage with the sensor housing proximal threaded end.
[0016] According to some embodiments, the at least one flex sensor
is an optic flex sensor configured to generate an optic signal, the
at least one communication channel being at least one optic
conductor, and wherein the at least one optic conductor is
detachably optically coupled to the at least one optic flex
sensor.
[0017] According to some embodiments, the at least one flex sensor
is coupled to the strut via at least one coupling member. According
to some embodiments, the at least one coupling member comprises at
least one of: a suture, a band, a tube, and/or a sleeve, and
wherein the at least one flex sensor is slidable relative to the at
least one coupling member upon application of a force exceeding the
frictional force applied by the at least one coupling member on the
at least one flex sensor.
[0018] According to some embodiments, the strut to which the at
least one flex sensor is coupled, comprises at least two strut
apertures through which the at least one flex sensor extends.
[0019] According to some embodiments, the at least one flex sensor
comprises a variable resistance element, configured to vary its
electrical resistivity in response to the extent of bending applied
thereto.
[0020] According to some embodiments, the variable resistance
element comprises a strain gauge.
[0021] According to some embodiments, the variable resistance
element comprises a conductive material layer.
[0022] According to some embodiments, the at least one flex sensor
is an optic flex sensor configured to generate an optic signal.
[0023] According to some embodiments, the at least one optic flex
sensor comprises a plurality of axially spaced Fiber Bragg
Gratings.
[0024] According to some embodiments, the delivery assembly further
comprises at least one optic conductor detachably optically coupled
to the at least one optic flex sensor.
[0025] According to some embodiments, the flex sensing assembly
further comprises at least one flexible distal extension, attached
to and extending distally from the at least one flex sensor.
[0026] According to some embodiments, the at least one flexible
distal extension is resiliently curved sideways.
[0027] According to some embodiments, the at least one flexible
distal extension comprises: a first flexible distal extension
comprising a first distal loop, wherein the first flexible distal
extension is attached to and extends distally from the first flex
sensor; and a second flexible distal extension comprising a second
distal loop, wherein the second flexible distal extension is
attached to and extends distally from the second flex sensor,
wherein the flex sensing assembly further comprises a flexible
elongate member extending distally from the handle and through the
first distal loop and the second distal loop, and wherein the
flexible elongate member is configured to couple the first flexible
distal extension with the second flexible distal extension when
extending through the first distal loop and the second distal loop,
and to allow separation thereof upon being pulled therefrom.
[0028] According to some embodiments, at least one of the at least
one flex sensors is coupled to at least two intersecting
struts.
[0029] According to some embodiments, the at least one flex sensor
comprises a first flex sensor coupled to a first strut, and a
second flex sensor coupled to the second strut, wherein the at
least one communication channel comprises a first communication
channel coupled to the first flex sensor, and a second
communication channel coupled to the second flex sensor, and
wherein the first strut and the second strut are intersecting with
each other.
[0030] According to some embodiments, the delivery assembly further
comprises: an inflatable balloon, the inflatable balloon positioned
within the prosthetic valve; a reservoir containing a predetermined
volume of inflation fluid; a pump in fluid communication with the
reservoir; and a fluid flow channel, a distal end of the fluid flow
channel in fluid communication with an opening of the inflatable
balloon and a proximal end of the fluid flow channel in fluid
communication with the pump, wherein, movement of the prosthetic
valve between the radially compressed configured to the radially
expanded configuration is responsive to an inflation of the
inflatable balloon, and wherein the pump is configured to generate
flow of the inflation fluid into the inflatable balloon via the
fluid flow channel.
[0031] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0032] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0033] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a
prosthetic valve comprising a plurality of intersecting struts, and
a delivery apparatus comprising: a handle; a delivery shaft
extending distally from the handle; and a flex sensing assembly,
comprising at least one flex sensor coupled to at least one of the
plurality of struts, wherein the prosthetic valve is movable
between a radially compressed configuration and a radially expanded
configuration, and wherein the at least one flex sensor comprises a
non-bending portion and a bending portion configured to flex
relative to the non-bending portion.
[0034] According to some embodiments, responsive to an output of
the at least one flex sensor, the control unit is configured to
generate a signal indicative of a diameter of the prosthetic
valve.
[0035] According to some embodiments, the prosthetic valve further
comprises at least one actuator assembly, wherein the delivery
apparatus further comprises an actuation member releasably coupled
to the at least one actuator assembly, and wherein the prosthetic
valve is expandable from the radially compressed state to the
radially expanded state upon actuating the at least one actuator
assembly by the at least one actuation member.
[0036] According to some embodiments, the non-bending portion of
the at least one flex sensor is coupled to the at least one
actuator assembly.
[0037] According to some embodiments, the delivery assembly further
comprises at least one communication channel, a first end of the at
least one communication channel coupled to the at least one flex
sensor and a second end of the at least one communication channel
extending towards the handle, wherein the at least one
communication channel is retractable from the prosthetic valve.
[0038] According to some embodiments, the flex sensing assembly
further comprises a sensor shaft extending distally from the
handle, and wherein at least a portion of the at least one
communication channel extends through the sensor shaft.
[0039] According to some embodiments, the delivery assembly further
comprises: at least one sensor housing attached to a strut; and at
least one detachable shaft extending distally from the handle, and
detachably coupled to the sensor housing, wherein the at least one
flex sensor is locally attached to the at least one sensor housing;
wherein at least a portion of the at least one communication
channel extends through the at least one detachable shaft; wherein
the communication channel is detachably coupled to the at least one
flex sensor; wherein the detachable shaft is configured isolate the
at least one communication channel from ambient flow, when the
detachable shaft is coupled to the sensor housing; and wherein the
at least one communication channel is axially movable relative to
the at least one detachable shaft, when the at least one
communication channel is detached from the at least one sensor.
[0040] According to some embodiments, the at least one
communication channel is detachable from the at least one flex
sensor upon application of a pull force on the at least one
communication channel, and wherein the magnitude of the pull force
is higher than a predetermined threshold magnitude.
[0041] According to some embodiments, wherein the sensor housing
comprises a sensor housing proximal threaded end, and wherein the
detachable shaft comprises a detachable shaft distal threaded end,
configured to engage with the sensor housing proximal threaded
end.
[0042] According to some embodiments, the at least one flex sensor
is an optic flex sensor configured to generate an optic signal, the
at least one communication channel being at least one optic
conductor, and wherein the at least one optic conductor is
detachably optically coupled to the at least one optic flex
sensor.
[0043] According to some embodiments, the at least one flex sensor
is coupled to the strut via at least one coupling member.
[0044] According to some embodiments, the at least one coupling
member comprises at least one of: a suture, a band, a tube, and/or
a sleeve, and wherein the at least one flex sensor is slidable
relative to the at least one coupling member upon application of a
force exceeding the frictional force applied by the at least one
coupling member on the at least one flex sensor.
[0045] According to some embodiments, the strut to which the at
least one flex sensor is coupled, comprises at least two strut
apertures through which the at least one flex sensor extends.
[0046] According to some embodiments, the at least one flex sensor
comprises a variable resistance element, configured to vary its
electrical resistivity in response to the extent of bending applied
thereto.
[0047] According to some embodiments, the variable resistance
element comprises a strain gauge.
[0048] According to some embodiments, the variable resistance
element comprises a conductive material layer.
[0049] According to some embodiments, the at least one flex sensor
is an optic flex sensor configured to generate an optic signal.
[0050] According to some embodiments, the at least one optic flex
sensor comprises a plurality of axially spaced Fiber Bragg
Gratings.
[0051] According to some embodiments, the delivery assembly further
comprises at least one optic conductor is detachably optically
coupled to the at least one optic flex sensor.
[0052] According to some embodiments, the flex sensing assembly
further comprises at least one flexible distal extension, attached
to and extending distally from the at least one flex sensor.
[0053] According to some embodiments, the at least one flexible
distal extension is resiliently curved sideways.
[0054] According to some embodiments, the at least one flexible
distal extension comprises: a first flexible distal extension
comprising a first distal loop, wherein the first flexible distal
extension is attached to and extends distally from the first flex
sensor; and a second flexible distal extension comprising a second
distal loop, wherein the second flexible distal extension is
attached to and extends distally from the second flex sensor,
wherein the flex sensing assembly further comprises a flexible
elongate member extending distally from the handle and through the
first distal loop and the second distal loop, and wherein the
flexible elongate member is configured to couple the first flexible
distal extension with the second flexible distal extension when
extending through the first distal loop and the second distal loop,
and to allow separation thereof upon being pulled therefrom.
[0055] According to some embodiments, at least one of the at least
one flex sensors is coupled to at least two intersecting
struts.
[0056] According to some embodiments, the at least one flex sensor
comprises a first flex sensor coupled to a first strut, and a
second flex sensor coupled to the second strut, wherein the at
least one communication channel comprises a first communication
channel coupled to the first flex sensor, and a second
communication channel coupled to the second flex sensor, and
wherein the first strut and the second strut are intersecting with
each other.
[0057] According to some embodiments, the delivery assembly further
comprises: an inflatable balloon, the inflatable balloon positioned
within the prosthetic valve; a reservoir containing a predetermined
volume of inflation fluid; a pump in fluid communication with the
reservoir; and a fluid flow channel, a distal end of the fluid flow
channel in fluid communication with an opening of the inflatable
balloon and a proximal end of the fluid flow channel in fluid
communication with the pump, wherein, movement of the prosthetic
valve between the radially compressed configured to the radially
expanded configuration is responsive to an inflation of the
inflatable balloon, and wherein the pump is configured to generate
flow of the inflation fluid into the inflatable balloon via the
fluid flow channel.
[0058] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0059] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0060] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a
prosthetic valve comprising a plurality of intersecting struts, and
a delivery apparatus comprising: a handle; a delivery shaft
extending distally from the handle; and a flex sensing assembly,
comprising: at least one flex sensor coupled to at least one of the
plurality of struts; and at least one communication channel, a
first end of the at least one communication channel coupled to the
at least one flex sensor and a second end of the at least one
communication channel extending towards the handle, wherein the
prosthetic valve is movable between a radially compressed
configuration and a radially expanded configuration, and wherein
the at least one communication channel is retractable from the
prosthetic valve.
[0061] According to some embodiments, the at least one flex sensor
comprises a non-bending portion and a bending portion configured to
flex relative to the non-bending portion.
[0062] According to some embodiments, the prosthetic valve further
comprises at least one actuator assembly, wherein the delivery
apparatus further comprises an actuation member releasably coupled
to the at least one actuator assembly, and wherein the prosthetic
valve is expandable from the radially compressed state to the
radially expanded state upon actuating the at least one actuator
assembly by the at least one actuation member.
[0063] According to some embodiments, the prosthetic valve further
comprises at least one actuator assembly, wherein the delivery
apparatus further comprises an actuation member releasably coupled
to the at least one actuator assembly, wherein the prosthetic valve
is expandable from the radially compressed state to the radially
expanded state upon actuating the at least one actuator assembly by
the at least one actuation member, and wherein the non-bending
portion of the at least one flex sensor is coupled to the at least
one actuator assembly.
[0064] According to some embodiments, the flex sensing assembly
further comprises a sensor shaft extending distally from the
handle, wherein at least a portion of the at least one
communication channel extends through the sensor shaft.
[0065] According to some embodiments, the delivery assembly further
comprises: at least one sensor housing attached to a strut; and at
least one detachable shaft extending distally from the handle, and
detachably coupled to the sensor housing, wherein the at least one
flex sensor is locally attached to the at least one sensor housing;
wherein at least a portion of the at least one communication
channel extends through the at least one detachable shaft; wherein
the communication channel is detachably coupled to the at least one
flex sensor; wherein the detachable shaft is configured isolate the
at least one communication channel from ambient flow, when the
detachable shaft is coupled to the sensor housing; and wherein the
at least one communication channel is axially movable relative to
the at least one detachable shaft, when the at least one
communication channel is detached from the at least one sensor.
[0066] According to some embodiments, the at least one
communication channel is detachable from the at least one flex
sensor upon application of a pull force on the at least one
communication channel, wherein the magnitude of the pull force is
higher than a predetermined threshold magnitude.
[0067] According to some embodiments, the sensor housing comprises
a sensor housing proximal threaded end, and wherein the detachable
shaft comprises a detachable shaft distal threaded end, configured
to engage with the sensor housing proximal threaded end.
[0068] According to some embodiments, the at least one flex sensor
is coupled to the strut via at least one coupling member.
[0069] According to some embodiments, the at least one coupling
member comprises at least one of: a suture, a band, a tube, and/or
a sleeve, and wherein the at least one flex sensor is slidable
relative to the at least one coupling member upon application of a
force exceeding the frictional force applied by the at least one
coupling member on the at least one flex sensor.
[0070] According to some embodiments, the strut to which the at
least one flex sensor is coupled comprises at least two strut
apertures through which the at least one flex sensor extends.
[0071] According to some embodiments, the at least one flex sensor
comprises a variable resistance element, configured to vary its
electrical resistivity in response to the extent of bending applied
thereto.
[0072] According to some embodiments, the variable resistance
element comprises a strain gauge.
[0073] According to some embodiments, the variable resistance
element comprises a conductive material layer.
[0074] According to some embodiments, the at least one flex sensor
is an optic flex sensor configured to generate an optic signal, and
wherein the at least one transmission line is an optic
conductor.
[0075] According to some embodiments, the at least one optic flex
sensor comprises a plurality of axially spaced Fiber Bragg
Gratings.
[0076] According to some embodiments, the at least one optic
conductor is detachably optically coupled to the at least one optic
flex sensor.
[0077] According to some embodiments, the flex sensing assembly
further comprises at least one flexible distal extension, attached
to and extending distally from the at least one flex sensor.
[0078] According to some embodiments, the at least one flexible
distal extension is resiliently curved sideways.
[0079] According to some embodiments, the at least one flexible
distal extension comprises: a first flexible distal extension
comprising a first distal loop, wherein the first flexible distal
extension is attached to and extends distally from the first flex
sensor; and a second flexible distal extension comprising a second
distal loop, wherein the second flexible distal extension is
attached to and extends distally from the second flex sensor,
wherein the flex sensing assembly further comprises a flexible
elongate member extending distally from the handle and through the
first distal loop and the second distal loop, and wherein the
flexible elongate member is configured to couple the first flexible
distal extension with the second flexible distal extension when
extending through the first distal loop and the second distal loop,
and to allow separation thereof upon being pulled therefrom.
[0080] According to some embodiments, at least one of the at least
one flex sensors is coupled to at least two intersecting
struts.
[0081] According to some embodiments, the at least one flex sensor
comprises a first flex sensor coupled to a first strut, and a
second flex sensor coupled to the second strut, wherein the at
least one communication channel comprises a first communication
channel coupled to the first flex sensor, and a second
communication channel coupled to the second flex sensor, and
wherein the first strut and the second strut are intersecting with
each other.
[0082] According to some embodiments, the delivery assembly further
comprises: an inflatable balloon, the inflatable balloon positioned
within the prosthetic valve; a reservoir containing a predetermined
volume of inflation fluid; a pump in fluid communication with the
reservoir; and a fluid flow channel, a distal end of the fluid flow
channel in fluid communication with an opening of the inflatable
balloon and a proximal end of the fluid flow channel in fluid
communication with the pump, wherein, movement of the prosthetic
valve between the radially compressed configured to the radially
expanded configuration is responsive to an inflation of the
inflatable balloon, and wherein the pump is configured to generate
flow of the inflation fluid into the inflatable balloon via the
fluid flow channel.
[0083] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0084] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0085] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a
prosthetic valve movable between a radially compressed
configuration and a radially expanded configuration, and a delivery
apparatus comprising: a handle; a delivery shaft extending distally
from the handle; an inflatable balloon, the inflatable balloon
positioned within the prosthetic valve; a reservoir containing a
predetermined volume of inflation fluid; a pump in fluid
communication with the reservoir; and a fluid flow channel, a
distal end of the fluid flow channel in fluid communication with an
opening of the inflatable balloon and a proximal end of the fluid
flow channel in fluid communication with the pump; a diameter
sensor, an output of the diameter sensor responsive to a radial
diameter of the prosthetic valve and/or the inflatable balloon; and
a control unit in communication with the pump and the diameter
sensor, wherein, responsive to an inflation of the inflatable
balloon, the prosthetic valve is movable between a radially
compressed configuration and a radially expanded configuration,
wherein the pump is configured to generate flow of the inflation
fluid into the inflatable balloon via the fluid flow channel, and
wherein, responsive to the output of the diameter sensor, the
control circuitry is configured to control the pump to adjust the
flow of the inflation fluid.
[0086] According to some embodiments, the control unit is further
configured, responsive to the output of the diameter sensor, to
determine an indication of a radial diameter of the prosthetic
valve and/or the inflatable balloon, the adjustment of the flow of
the inflation fluid further responsive to the determined diameter
indication.
[0087] According to some embodiments, the determined diameter
indication comprises a change in radial diameter.
[0088] According to some embodiments, the diameter sensor
comprises: at least one radially translatable member juxtaposed
with an outer surface of the inflatable balloon such that the
inflation of the balloon radially translates the at least one
radially translatable member; and a linear displacement sensor
coupled to the at least one radially translatable member and in
communication with the control unit, an output of the linear
displacement sensor configured to be responsive to the radial
translation of the at least one radially translatable member.
[0089] According to some embodiments, the at least one radially
translatable member surrounds the outer surface of the inflatable
balloon.
[0090] According to some embodiments, the at least one radially
translatable member is loop shaped.
[0091] According to some embodiments, the at least one radially
translatable member comprises: a first balloon portion; a second
balloon portion; and a connection portion, each of the first
balloon portion and the second balloon portion extending from a
first end of the connection portion, and a second end of the
connection portion coupled to the linear displacement sensor.
[0092] According to some embodiments, each of the first balloon
portion and the second balloon portion extends in a respective
direction, the direction of extension of the second balloon portion
generally opposing the direction of extension of the first balloon
portion.
[0093] According to some embodiments, the diameter sensor comprises
at least one flex sensor, wherein the prosthetic valve comprises a
plurality of intersecting struts, the at least one flex sensor
coupled to at least one of the plurality of struts.
[0094] According to some embodiments, the at least one flex sensor
comprises a non-bending portion and a bending portion configured to
flex relative to the non-bending portion.
[0095] According to some embodiments, the at least one flex sensor
comprises a first flex sensor coupled to a first of the plurality
of struts and a second flex sensor coupled to a second of a
plurality of struts, wherein the first of the plurality of struts
and the second of the plurality of struts intersect each other.
[0096] According to some embodiments, the delivery assembly further
comprises at least one communication channel, a first end of the at
least one communication channel coupled to the at least one flex
sensor, wherein the at least one communication channel is
retractable from the prosthetic valve.
[0097] According to some embodiments, the diameter sensor comprises
at least one strain gauge circumferentially disposed on an outer
surface of the inflatable balloon.
[0098] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0099] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein the adjustment of the flow of the
inflation fluid is responsive to a predetermined function of the
measured pressure and the determined diameter indication.
[0100] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0101] According to some embodiments, the pressure sensor is
positioned within the fluid flow channel.
[0102] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a
prosthetic valve movable between a radially compressed
configuration and a radially expanded configuration, and a delivery
apparatus comprising: a handle; a delivery shaft extending distally
from the handle; an inflatable balloon, the inflatable balloon
positioned within the prosthetic valve; a reservoir containing a
predetermined volume of inflation fluid; a pump in fluid
communication with the reservoir; a fluid flow channel, a distal
end of the fluid flow channel in fluid communication with an
opening of the inflatable balloon and a proximal end of the fluid
flow channel in fluid communication with the pump; an imager
configured to image the prosthetic valve; and a control unit in
communication with the pump and the imager, wherein, responsive to
an inflation of the inflatable balloon, the prosthetic valve is
movable between a radially compressed configuration and a radially
expanded configuration, wherein the pump is configured to generate
flow of the inflation fluid into the inflatable balloon via the
fluid flow channel, and wherein, responsive to the output of the
imager, the control circuitry is configured to control the pump to
adjust the flow of the inflation fluid.
[0103] According to some embodiments, the prosthetic valve
comprises at least one radiopaque marker, the configuration of the
imager to image the prosthetic valve comprises a configuration to
image the at least one radiopaque marker.
[0104] According to some embodiments, the at least one radiopaque
marker comprises radiopaque coating.
[0105] According to some embodiments, the at least one radiopaque
marker comprises a plurality of radiopaque markers exhibiting
predetermined spaces therebetween.
[0106] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0107] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein the adjustment of the flow of the
inflation fluid is responsive to a predetermined function of the
measured pressure and the determined diameter indication.
[0108] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0109] According to some embodiments, the pressure sensor is
positioned within the fluid flow channel.
[0110] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a
prosthetic valve movable between a radially compressed
configuration and a radially expanded configuration, and a delivery
apparatus comprising: a handle; a delivery shaft extending distally
from the handle; an inflatable balloon, the inflatable balloon
positioned within the prosthetic valve; a reservoir containing a
predetermined volume of inflation fluid; a pump in fluid
communication with the reservoir; a fluid flow channel, a distal
end of the fluid flow channel in fluid communication with an
opening of the inflatable balloon and a proximal end of the fluid
flow channel in fluid communication with the pump; an imager
configured to image the inflatable balloon; and a control unit in
communication with the pump and the imager, wherein, responsive to
an inflation of the inflatable balloon, the prosthetic valve is
movable between a radially compressed configuration and a radially
expanded configuration, wherein the pump is configured to generate
flow of the inflation fluid into the inflatable balloon via the
fluid flow channel, and wherein, responsive to the output of the
imager, the control circuitry is configured to control the pump to
adjust the flow of the inflation fluid.
[0111] According to some embodiments, the inflatable balloon
comprises at least one radiopaque marker, the configuration of the
imager to image the inflatable balloon comprises a configuration to
image the at least one radiopaque marker.
[0112] According to some embodiments, wherein the at least one
radiopaque marker comprises radiopaque coating.
[0113] According to some embodiments, the at least one radiopaque
marker comprises a plurality of radiopaque markers exhibiting
predetermined spaces therebetween.
[0114] According to some embodiments, the control unit is further
configured, responsive to the output of the imager, to determine an
indication of a radial diameter of the prosthetic valve and/or the
inflatable balloon, the adjustment of the flow of the inflation
fluid further responsive to the determined diameter indication.
[0115] According to some embodiments, the determined diameter
indication comprises a change in radial diameter.
[0116] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0117] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein the adjustment of the flow of the
inflation fluid is responsive to a predetermined function of the
measured pressure and the determined diameter indication.
[0118] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0119] According to some embodiments, the pressure sensor is
positioned within the fluid flow channel.
[0120] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a handle; a
delivery shaft extending distally from the handle; an inflatable
balloon; a reservoir containing a predetermined volume of inflation
fluid; a pump in fluid communication with the reservoir; a fluid
flow channel, a distal end of the fluid flow channel in fluid
communication with an opening of the inflatable balloon and a
proximal end of the fluid flow channel in fluid communication with
the pump, a control unit in communication with the pump; at least
one radially translatable member juxtaposed with an outer surface
of the inflatable balloon such that the inflation of the balloon
radially translates the at least one radially translatable member;
and a linear displacement sensor coupled to the at least one
radially translatable member and in communication with the control
unit, an output of the linear displacement sensor configured to be
responsive to the radial translation of the at least one radially
translatable member, wherein the pump is configured to generate
flow of the inflation fluid into the inflatable balloon via the
fluid flow channel, and wherein, responsive to the output of the
linear displacement sensor, the control circuitry is configured to
control the pump to adjust the flow of the inflation fluid.
[0121] According to some embodiments, the control unit is further
configured, responsive to the output of the linear displacement
sensor, to determine an indication of a radial diameter of the
prosthetic valve and/or the inflatable balloon, the adjustment of
the flow of the inflation fluid further responsive to the
determined diameter indication.
[0122] According to some embodiments, the determined diameter
indication comprises a change in radial diameter.
[0123] According to some embodiments, the at least one radially
translatable member surrounds the outer surface of the inflatable
balloon.
[0124] According to some embodiments, the at least one radially
translatable member is loop shaped.
[0125] According to some embodiments, the at least one radially
translatable member comprises: a first balloon portion; a second
balloon portion; and a connection portion, each of the first
balloon portion and the second balloon portion extending from a
first end of the connection portion, and a second end of the
connection portion coupled to the linear displacement sensor.
[0126] According to some embodiments, each of the first balloon
portion and the second balloon portion extends in a respective
direction, the direction of extension of the second balloon portion
generally opposing the direction of extension of the first balloon
portion.
[0127] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0128] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein the adjustment of the flow of the
inflation fluid is responsive to a predetermined function of the
measured pressure and the determined diameter indication.
[0129] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0130] According to some embodiments, the pressure sensor is
positioned within the fluid flow channel.
[0131] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a handle; a
delivery shaft extending distally from the handle; an inflatable
balloon; a reservoir containing a predetermined volume of inflation
fluid; a pump in fluid communication with the reservoir; a fluid
flow channel, a distal end of the fluid flow channel in fluid
communication with an opening of the inflatable balloon and a
proximal end of the fluid flow channel in fluid communication with
the pump; a control unit in communication with the pump; and at
least one strain gauge circumferentially disposed on an outer
surface of the inflatable balloon, wherein the pump is configured
to generate flow of the inflation fluid into the inflatable balloon
via the fluid flow channel, and wherein, responsive to an output of
the at least one strain gauge, the control circuitry is configured
to control the pump to adjust the flow of the inflation fluid.
[0132] According to some embodiments, the control unit is further
configured, responsive to the output of the at least one strain
gauge, to determine an indication of a radial diameter of the
inflatable balloon, the adjustment of the flow of the inflation
fluid further responsive to the determined diameter indication.
[0133] According to some embodiments, the determined diameter
indication comprises a comprises a change in radial diameter.
[0134] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0135] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein the adjustment of the flow of the
inflation fluid is responsive to a predetermined function of the
measured pressure and the determined diameter indication.
[0136] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0137] According to some embodiments, the pressure sensor is
positioned within the fluid flow channel.
[0138] According to another aspect of the invention, a delivery
assembly is provided, the delivery assembly comprising: a handle; a
delivery shaft extending distally from the handle; an inflatable
balloon, the inflatable balloon positioned within the prosthetic
valve; a reservoir containing a predetermined volume of inflation
fluid; a pump in fluid communication with the reservoir; a fluid
flow channel, a distal end of the fluid flow channel in fluid
communication with an opening of the inflatable balloon and a
proximal end of the fluid flow channel in fluid communication with
the pump; an imager configured to image the inflatable balloon; and
a control unit in communication with the pump and the imager,
wherein the pump is configured to generate flow of the inflation
fluid into the inflatable balloon via the fluid flow channel, and
wherein, responsive to the output of the imager, the control
circuitry is configured to control the pump to adjust the flow of
the inflation fluid.
[0139] According to some embodiments, the inflatable balloon
comprises at least one radiopaque marker, the configuration of the
imager to image the inflatable balloon comprises a configuration to
image the at least one radiopaque marker.
[0140] According to some embodiments, the at least one radiopaque
marker comprises radiopaque coating.
[0141] According to some embodiments, the at least one radiopaque
marker comprises a plurality of radiopaque markers exhibiting
predetermined spaces therebetween.
[0142] According to some embodiments, the control unit is further
configured, responsive to the output of the imager, to determine an
indication of a radial diameter of the inflatable balloon, the
adjustment of the flow of the inflation fluid further responsive to
the determined diameter indication.
[0143] According to some embodiments, the determined diameter
indication comprises a change in radial diameter.
[0144] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein, responsive to the measured pressure of
the inflation fluid, the pump is further configured to adjust the
generated flow of the inflation fluid.
[0145] According to some embodiments, the delivery assembly further
comprises a pressure sensor configured to measure pressure of the
inflation fluid, wherein the adjustment of the flow of the
inflation fluid is responsive to a predetermined function of the
measured pressure and the determined diameter indication.
[0146] According to some embodiments, the pressure sensor is
positioned within the inflation fluid.
[0147] According to some embodiments, the pressure sensor is
positioned within the fluid flow channel.
[0148] According to another aspect of the invention, a delivery
method for a prosthetic valve comprising a plurality of
intersecting struts is provided, the method comprising: coupling at
least one flex sensor to at least one of the plurality of struts;
delivering the prosthetic valve to a predetermined anatomical
location; moving the delivered prosthetic valve between a radially
compressed configuration and a radially expanded configuration; and
responsive to an output of the at least one flex sensor, generating
a signal indicative of a diameter of the prosthetic valve.
[0149] According to some embodiments, the at least one flex sensor
comprises a non-bending portion and a bending portion configured to
flex relative to the non-bending portion.
[0150] According to some embodiments, the method further comprises
retracting at least one communication channel from the prosthetic
valve, the at least one communication channel coupled to the at
least one flex sensor.
[0151] According to some embodiments, the method further comprises
applying a pull force on the at least one communication channel,
the magnitude of the pull force higher than predetermined threshold
magnitude, wherein the at least one communication channel is
detachable from the at least one flex sensor upon the application
of the pull force.
[0152] According to some embodiments, at least one of the at least
one flex sensors is coupled to at least two intersecting
struts.
[0153] According to some embodiments, the coupling of the at least
one flex sensor to the at least one strut comprises: coupling a
first of the at least one flex sensor to a first of the at least
one strut; and coupling a second of the at least one flex sensor to
a second of the at least one strut, wherein the first strut and the
second strut are intersecting with each other.
[0154] According to some embodiments, the method further comprises
pumping inflation fluid into an inflatable balloon positioned
within the prosthetic valve, the pumped inflation fluid expanding
the inflatable balloon thereby causing the moving of the delivered
prosthetic valve from the radially compressed configuration to the
radially expanded configuration.
[0155] According to another aspect of the invention, a delivery
method for a prosthetic valve comprising a plurality of
intersecting struts is provided, the method comprising: coupling at
least one flex sensor to at least one of the plurality of struts;
delivering the prosthetic valve to a predetermined anatomical
location; and moving the delivered prosthetic valve between a
radially compressed configuration and a radially expanded
configuration, wherein the moving to the radially expanded
configuration flexes a bending portion of the at least one flex
sensor relative to a non-bending portion of the at least one flex
sensor.
[0156] According to some embodiments, the method further comprises,
responsive to an output of the at least one flex sensor, generating
a signal indicative of a diameter of the prosthetic valve.
[0157] According to some embodiments, the method further comprises
retracting at least one communication channel from the prosthetic
valve, the at least one communication channel coupled to the at
least one flex sensor.
[0158] According to some embodiments, the method further comprises
applying a pull force on the at least one communication channel,
the magnitude of the pull force higher than predetermined threshold
magnitude, wherein the at least one communication channel is
detachable from the at least one flex sensor upon the application
of the pull force.
[0159] According to some embodiments, at least one of the at least
one flex sensors is coupled to at least two intersecting
struts.
[0160] According to some embodiments, the coupling of the at least
one flex sensor to the at least one strut comprises: coupling a
first of the at least one flex sensor to a first of the at least
one strut; and coupling a second of the at least one flex sensor to
a second of the at least one strut, wherein the first strut and the
second strut are intersecting with each other.
[0161] According to some embodiments, the method further comprises
pumping inflation fluid into an inflatable balloon positioned
within the prosthetic valve, the pumped inflation fluid expanding
the inflatable balloon thereby causing the moving of the delivered
prosthetic valve from the radially compressed configuration to the
radially expanded configuration.
[0162] According to another aspect of the invention, a delivery
method for a prosthetic valve comprising a plurality of
intersecting struts is provided, the method comprising: coupling at
least one flex sensor to at least one of the plurality of struts, a
communication channel coupled to the at least one flex sensor;
delivering the prosthetic valve to a predetermined anatomical
location; moving the delivered prosthetic valve between a radially
compressed configuration and a radially expanded configuration; and
subsequent to the moving to the radially expanded configuration,
retracting the communication channel from the prosthetic valve.
[0163] According to some embodiments, the method further comprises,
responsive to an output of the at least one flex sensor, generating
a signal indicative of a diameter of the prosthetic valve.
[0164] According to some embodiments, the at least one flex sensor
comprises a non-bending portion and a bending portion configured to
flex relative to the non-bending portion.
[0165] According to some embodiments, the method further comprises
applying a pull force on the at least one communication channel,
the magnitude of the pull force higher than predetermined threshold
magnitude, wherein the at least one communication channel is
detachable from the at least one flex sensor upon the application
of the pull force.
[0166] According to some embodiments, at least one of the at least
one flex sensors is coupled to at least two intersecting
struts.
[0167] According to some embodiments, the coupling of the at least
one flex sensor to the at least one strut comprising: coupling a
first of the at least one flex sensor to a first of the at least
one strut; and coupling a second of the at least one flex sensor to
a second of the at least one strut, and wherein the first strut and
the second strut are intersecting with each other.
[0168] According to some embodiments, the method further comprises
pumping inflation fluid into an inflatable balloon positioned
within the prosthetic valve, the pumped inflation fluid expanding
the inflatable balloon thereby causing the moving of the delivered
prosthetic valve from the radially compressed configuration to the
radially expanded configuration.
[0169] According to another aspect of the invention, a delivery
method for a prosthetic valve is provided, the method comprising:
delivering the prosthetic valve to a predetermined anatomical
location; pumping inflation fluid into an inflatable balloon
positioned within the prosthetic valve, the pumped inflation fluid
inflating the inflatable balloon thereby causing the delivered
prosthetic valve to be moved from a radially compressed
configuration to a radially expanded configuration; determining an
indication of a radial diameter of the prosthetic valve and/or the
inflatable balloon; and responsive to the determined radial
diameter indication, adjusting the flow of the inflation fluid.
[0170] According to some embodiments, the determining the diameter
indication comprises determining a change in the radial
diameter.
[0171] According to some embodiments, the method further comprises:
juxtaposing at least one radially translatable member with an outer
surface of the inflatable balloon such that the inflation of the
balloon radially translates the at least one radially translatable
member, wherein the radial diameter indication is responsive to a
linear displacement sensor coupled to the at least one radially
translatable member, an output of the linear displacement sensor
configured to be responsive to the radial translation of the at
least one radially translatable member.
[0172] According to some embodiments, the juxtaposing comprises
surrounding the outer surface of the inflatable balloon.
[0173] According to some embodiments, the method further comprises,
responsive to the output of the linear displacement sensor,
determining an indication of a diameter of the prosthetic valve,
the adjustment of the flow of the inflation fluid further
responsive to the determined diameter indication.
[0174] According to some embodiments, the method further comprises:
juxtaposing at least one strain gauge with an outer surface of the
inflatable balloon, wherein the radial diameter indication is
responsive to an output of the at least one strain gauge.
[0175] According to some embodiments, the method further comprises
imaging the prosthetic valve, wherein the radial diameter
indication is responsive to the imaging of the prosthetic
valve.
[0176] According to some embodiments, the method further comprises
positioning at least one radiopaque marker on the prosthetic valve,
the imaging of the prosthetic valve comprising imaging the
positioned at least one radiopaque marker.
[0177] According to some embodiments, the method further comprises
imaging the inflatable balloon, wherein the radial diameter
indication is responsive to the imaging of the inflatable
balloon.
[0178] According to some embodiments, the method further comprises
positioning at least one radiopaque marker on the inflatable
balloon, the imaging of the prosthetic valve comprising imaging the
positioned at least one radiopaque marker.
[0179] According to some embodiments, the method further comprises:
measuring pressure of the inflation fluid; and responsive to the
measured pressure, adjusting the flow of the inflation fluid.
[0180] According to some embodiments, the method further comprises
coupling at least one flex sensor to at least one of a plurality of
struts of the prosthetic valve, wherein the radial diameter
indication is responsive to an output of the at least one flex
sensor.
[0181] According to some embodiments, the at least one flex sensor
comprises a non-bending portion and a bending portion configured to
flex relative to the non-bending portion.
[0182] According to some embodiments, the method further comprises
retracting at least one communication channel from the prosthetic
valve, the at least one communication channel coupled to the at
least one flex sensor.
[0183] According to some embodiments, the method further comprises:
measuring pressure of the inflation fluid; and responsive to a
predetermined function of the determined diameter indication and
measured pressure, adjusting the flow of the inflation fluid.
[0184] According to another aspect of the invention, a delivery
method for an inflatable balloon is provided, the method
comprising: delivering an inflatable balloon to a predetermined
anatomical location; pumping inflation fluid into the delivered
inflatable balloon, the pumped inflation fluid inflating the
inflatable balloon; juxtaposing at least one radially translatable
member with an outer surface of the inflatable balloon such that
the inflation of the balloon radially translates the at least one
radially translatable member; and responsive to a linear
displacement sensor coupled to the at least one radially
translatable member, adjusting the flow of the inflation fluid,
wherein an output of the linear displacement sensor is configured
to be responsive to the radial translation of the at least one
radially translatable member.
[0185] According to some embodiments, the juxtaposing comprises
surrounding the outer surface of the inflatable balloon.
[0186] According to some embodiments, the method further comprises,
responsive to the output of the linear displacement sensor,
determining an indication of a diameter of the prosthetic valve,
the adjustment of the flow of the inflation fluid further
responsive to the determined diameter indication.
[0187] According to some embodiments, the determining the radial
diameter indication comprises determining a change in the radial
diameter.
[0188] According to some embodiments, the method further comprises
measuring pressure of the inflation fluid, wherein the adjustment
of the flow of the inflation fluid is further responsive to a
predetermined function of the determined diameter indication and
the measured pressure.
[0189] According to some embodiments, the method further comprises
measuring pressure of the inflation fluid, wherein the adjustment
of the flow of the inflation fluid is further responsive to the
measured pressure.
[0190] According to another aspect of the invention, a delivery
method for an inflatable balloon is provided, the method
comprising: delivering an inflatable balloon to a predetermined
anatomical location; pumping inflation fluid into the delivered
inflatable balloon, the pumped inflation fluid inflating the
inflatable balloon; juxtaposing a strain gauge with an outer
surface of the inflatable balloon; and responsive to an output of
the strain gauge, adjusting the flow of the inflation fluid.
[0191] According to some embodiments, the method further comprises,
responsive to an output of the at least one strain gauge,
determining an indication of a diameter of the inflatable balloon,
the adjustment of the flow of the inflation fluid further
responsive to the determined diameter indication.
[0192] According to some embodiments, the determining the radial
diameter indication comprises determining a change in the radial
diameter.
[0193] According to some embodiments, the method further comprises
measuring pressure of the inflation fluid, wherein the adjustment
of the flow of the inflation fluid is further responsive to a
predetermined function of the determined diameter indication and
the measured pressure.
[0194] According to some embodiments, the method further comprises
measuring pressure of the inflation fluid, wherein the adjustment
of the flow of the inflation fluid is further responsive to the
measured pressure.
[0195] According to another aspect of the invention, a delivery
method for an inflatable balloon is provided, the method
comprising: delivering an inflatable balloon to a predetermined
anatomical location; pumping inflation fluid into the delivered
inflatable balloon, the pumped inflation fluid inflating the
inflatable balloon; imaging the inflatable balloon; and responsive
to the imaging, adjusting the flow of the inflation fluid.
[0196] According to some embodiments, the method further comprises
positioning at least one radiopaque marker on the inflatable
balloon, the imaging of the prosthetic valve comprising imaging the
positioned at least one radiopaque marker.
[0197] According to some embodiments, the method further comprises,
responsive to the imaging, determining an indication of a diameter
of the inflatable balloon, the adjustment of the flow of the
inflation fluid further responsive to the determined diameter
indication.
[0198] According to some embodiments, the method further comprises:
measuring pressure of the inflation fluid, wherein the adjustment
of the flow of the inflation fluid is further responsive to the
measured pressure.
[0199] According to some embodiments, the method further comprises
measuring pressure of the inflation fluid, wherein the adjustment
of the flow of the inflation fluid is further responsive to a
predetermined function of the determined diameter indication and
measured pressure.
[0200] Certain embodiments of the present invention may include
some, all, or none of the above advantages. Further advantages may
be readily apparent to those skilled in the art from the figures,
descriptions, and claims included herein. Aspects and embodiments
of the invention are further described in the specification herein
below and in the appended claims.
[0201] Unless otherwise defined, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention pertains. In case
of conflict, the patent specification, including definitions,
governs. As used herein, the indefinite articles "a" and "an" mean
"at least one" or "one or more" unless the context clearly dictates
otherwise.
[0202] The following embodiments and aspects thereof are described
and illustrated in conjunction with systems, tools and methods
which are meant to be exemplary and illustrative, but not limiting
in scope. In various embodiments, one or more of the
above-described problems have been reduced or eliminated, while
other embodiments are directed to other advantages or
improvements.
BRIEF DESCRIPTION OF THE FIGURES
[0203] Some embodiments of the invention are described herein with
reference to the accompanying figures. The description, together
with the figures, makes apparent to a person having ordinary skill
in the art how some embodiments may be practiced. The figures are
for the purpose of illustrative description and no attempt is made
to show structural details of an embodiment in more detail than is
necessary for a fundamental understanding of the invention. For the
sake of clarity, some objects depicted in the figures are not to
scale.
[0204] In the Figures:
[0205] FIG. 1 shows a view in perspective of a delivery assembly
comprising a delivery apparatus carrying a prosthetic valve,
according to some embodiments.
[0206] FIGS. 2A and 2B show in perspective view a prosthetic valve,
according to some embodiments.
[0207] FIG. 3A shows a view in perspective of an inner member,
according to some embodiments.
[0208] FIG. 3B shows a view in perspective of an actuator assembly,
according to some embodiments.
[0209] FIG. 3C shows a view in perspective of a prosthetic valve
including multiple actuator assemblies of the type shown in FIG.
3B.
[0210] FIGS. 4A-4C show an actuator assembly of the type shown in
FIG. 3B in different operational states thereof.
[0211] FIGS. 5A-5C show different stages of utilizing a delivery
assembly equipped with a flex sensing assembly, according to some
embodiments.
[0212] FIG. 6A shows a zoomed-in view of a flex sensing assembly
equipped with a single flex sensor coupled to a single strut,
according to some embodiments.
[0213] FIG. 6B shows a zoomed-in view of a flex sensing assembly
equipped with two flex sensor coupled to two intersecting struts,
according to some embodiments.
[0214] FIG. 7 shows a zoomed-in view of a flex sensing assembly
equipped with a single flex sensor coupled to two intersecting
struts, according to some embodiments.
[0215] FIG. 8 shows a flex sensing assembly coupled to an actuator
assembly, according to some embodiments.
[0216] FIGS. 9A-9C show different views of a delivery assembly
equipped with optic fiber assemblies, according to some
embodiments.
[0217] FIGS. 10A-10C show different operational states of a
detachable coupling mechanism between communication channels and
flex sensors, according to some embodiments.
[0218] FIGS. 11A-11B show different states of a flex sensing
assembly having flexible distal extension extending from the flex
sensors, according to some embodiments.
[0219] FIGS. 12A-12B show different states of a flex sensing
assembly equipped with flex sensors that include strain gauges,
according to some embodiments.
[0220] FIGS. 13A-13B show different states of a flex sensing
assembly equipped with flex sensors that include conductive
material layers, according to some embodiments.
[0221] FIGS. 14A-E shows different stages of utilizing a flex
sensing assembly equipped with a flexible elongated member,
according to some embodiments.
[0222] FIG. 15 shows a view in perspective of a frame of a balloon
expandable valve, according to some embodiments.
[0223] FIG. 16 shows a view in perspective of a delivery assembly
for delivery and implantation of a balloon expandable valve,
according to some embodiments.
[0224] FIGS. 17A-17B show different configurations of the balloon
expandable valve of FIG. 16.
[0225] FIGS. 18A-18B show a side view of a first embodiment of a
radially translatable member coupled to a linear displacement
sensor.
[0226] FIG. 19 shows a side view of the first embodiment of the
radially translatable member of FIGS. 18A-18B positioned within a
sleeve.
[0227] FIG. 20 shows a side view of a second embodiment of a
radially translatable member.
[0228] FIG. 21 shows the delivery assembly of FIG. 16, further
comprising an imager, according to some embodiments.
[0229] FIG. 22A shows radiopaque markers positioned on an
inflatable balloon, according to some embodiments.
[0230] FIG. 22B shows radiopaque markers positioned on the frame of
a prosthetic valve, according to some embodiments.
[0231] FIG. 23 shows a side view of an inflatable balloon with a
strain gauge, according to certain embodiments.
[0232] FIGS. 24A-24C show high level flow charts of various
deployment methods for a prosthetic valve, utilizing at least one
flex sensor, according to some embodiments.
[0233] FIGS. 25A-25B show high level flow charts of various
deployment methods for a prosthetic valve, utilizing a
pump-inflatable balloon, according to some embodiments.
DETAILED DESCRIPTION
[0234] In the following description, various aspects of the
disclosure will be described. For the purpose of explanation,
specific configurations and details are set forth in order to
provide a thorough understanding of the different aspects of the
disclosure. However, it will also be apparent to one skilled in the
art that the disclosure may be practiced without specific details
being presented herein. Furthermore, well-known features may be
omitted or simplified in order not to obscure the disclosure. In
the figures, like reference numerals refer to like parts
throughout. In order to avoid undue clutter from having too many
reference numbers and lead lines on a particular drawing, some
components will be introduced via one or more drawings and not
explicitly identified in every subsequent drawing that contains
that component.
[0235] FIG. 1 shows a view in perspective of a delivery assembly
100, according to some embodiments. The delivery assembly 100 can
include a prosthetic valve 114 and a delivery apparatus 102. The
prosthetic valve 114 can be on or releasably coupled to the
delivery apparatus 102. The delivery apparatus can include a handle
110 at a proximal end thereof, a nosecone shaft 108 extending
distally from the handle 110, a nosecone 109 attached to the distal
end of the nosecone shaft 108, a delivery shaft 106 extending over
the nosecone shaft 108, and optionally an outer shaft 104 extending
over the delivery shaft 106.
[0236] The term "proximal", as used herein, generally refers to the
side or end of any device or a component of a device, which is
closer to the handle 110 or an operator of the handle 110 when in
use.
[0237] The term "distal", as used herein, generally refers to the
side or end of any device or a component of a device, which is
farther from the handle 110 or an operator of the handle 110 when
in use.
[0238] The term "prosthetic valve", as used herein, refers to any
type of a prosthetic valve deliverable to a patient's target site
over a catheter, which is radially expandable and compressible
between a radially compressed, or crimped, state, and a radially
expanded state. Thus, a prosthetic valve 114 can be crimped or
retained by a delivery apparatus 102 in a compressed state during
delivery, and then expanded to the expanded state once the
prosthetic valve 114 reaches the implantation site. The expanded
state may include a range of diameters to which the valve may
expand, between the compressed state and a maximal diameter reached
at a fully expanded state. Thus, a plurality of partially expanded
states may relate to any expansion diameter between radially
compressed or crimped state, and maximally expanded state.
[0239] The term "plurality", as used herein, means more than
one.
[0240] A prosthetic valve 114 of the current disclosure may include
any prosthetic valve configured to be mounted within the native
aortic valve, the native mitral valve, the native pulmonary valve,
and the native tricuspid valve. While a delivery assembly 100
described in the current disclosure, includes a delivery apparatus
102 and a prosthetic valve 114, it should be understood that the
delivery apparatus 102 according to any embodiment of the current
disclosure can be used for implantation of other prosthetic devices
aside from prosthetic valves, such as stents or grafts.
[0241] A catheter deliverable prosthetic valve 114 can be delivered
to the site of implantation via the delivery assembly 100 carrying
the valve 114 in a radially compressed or crimped state, toward the
target site, to be mounted against the native anatomy, by expanding
the prosthetic valve 114 via various expansion mechanisms. Balloon
expandable valves generally involve a procedure of inflating a
balloon within a prosthetic valve, thereby expanding the prosthetic
valve 114 within the desired implantation site. Once the valve is
sufficiently expanded, the balloon is deflated and retrieved along
with the delivery apparatus 102. Self-expandable valves include a
frame that is shape-set to automatically expand as soon an outer
retaining capsule, which may be also defined as the distal portion
of an outer shaft (104) or the distal portion of a delivery shaft
(106), is withdrawn proximally relative to the prosthetic valve.
Mechanically expandable valves are a category of prosthetic valves
that rely on a mechanical actuation mechanism for expansion. The
mechanical actuation mechanism usually includes a plurality of
expansion and locking assemblies, releasably coupled to respective
actuation assemblies of the delivery apparatus 102, controlled via
the handle 110 for actuating the expansion and locking assemblies
to expand the prosthetic valve to a desired diameter. The expansion
and locking assemblies may optionally lock the valve's diameter to
prevent undesired recompression thereof, and disconnection of the
actuation assemblies from the expansion and locking assemblies, to
enable retrieval of the delivery apparatus 102 once the prosthetic
valve is properly positioned at the desired site of
implantation.
[0242] The delivery assembly 100 can be utilized, for example, to
deliver a prosthetic aortic valve for mounting against the aortic
annulus, to deliver a prosthetic mitral valve for mounting against
the mitral annulus, or to deliver a prosthetic valve for mounting
against any other native annulus.
[0243] The exemplary delivery assembly 100 illustrated in FIG. 1
may be a delivery assembly 100.sup.a comprising a delivery
apparatus 102.sup.a for delivery and implantation of a mechanically
expandable valve 114.sup.a. According to some embodiments, the
delivery apparatus 102.sup.a includes a balloon catheter 24 having
an inflatable balloon (hidden from view) mounted on its distal end.
The balloon expandable prosthetic valve 100.sup.a can be carried in
a crimped state over the inflatable balloon, as shown in FIG. 1.
Optionally, an outer shaft 20 can concentrically extend over the
balloon catheter 24.
[0244] According to some embodiments, the prosthetic valve 114 is a
mechanically expandable valve 114.sup.a, and the delivery assembly
100 illustrated in FIG. 1 may be a delivery assembly 100.sup.a
comprising a delivery apparatus 102.sup.a for delivery and
implantation of a mechanically expandable valve 114.sup.a.
According to some embodiments, the delivery apparatus 102.sup.a
further comprises a plurality of actuation assemblies 150 extending
from the handle 110.sup.a through the delivery shaft 106.sup.a. The
actuation assemblies 150 can generally include actuators 151
(hidden from view in FIG. 1, visible in FIGS. 4A-4C) releasably
coupled at their distal ends to respective expansion and locking
assemblies 134 of the mechanically expandable valve 114.sup.a, and
sleeves 153 (annotated in FIG. 3) disposed around the respective
actuators 151. Each actuator 151 may be axially movable relative to
the sleeve 153 covering it.
[0245] The mechanically expandable valve 114.sup.a can be delivered
to the site of implantation via a delivery assembly 100.sup.a
carrying the valve 114.sup.a in a radially compressed or crimped
state, toward the target site, to be mounted against the native
anatomy, by expanding the valve 114.sup.a via a mechanical
expansion mechanism, as will be elaborated below.
[0246] The nosecone 109 can be connected to the distal end of the
nosecone shaft 108. A guidewire (not shown) can extend through a
central lumen of the nosecone shaft 108 and an inner lumen of the
nosecone 109, so that the delivery apparatus 102 can be advanced
over the guidewire through the patient's vasculature.
[0247] A distal end portion of the outer shaft 104 can extend over
the prosthetic valve 114 and contact the nosecone 109 in a delivery
configuration of the delivery apparatus 102. Thus, the distal end
portion of the outer shaft 104 can serve as a delivery capsule that
contains, or houses, the prosthetic valve 114 in a radially
compressed or crimped configuration for delivery through the
patient's vasculature.
[0248] The outer shaft 104 and the delivery shaft 106 can be
configured to be axially movable relative to each other, such that
a proximally oriented movement of the outer shaft 104 relative to
the delivery shaft 106, or a distally oriented movement of the
delivery shaft 106 relative to the outer shaft 104, can expose the
prosthetic valve from the outer shaft 104. In alternative
embodiments, the prosthetic valve 114 is not housed within the
outer shaft 104 during delivery. Thus, according to some
embodiments, the delivery apparatus 102 does not include an outer
shaft 104.
[0249] As mentioned above, the proximal ends of the nosecone shaft
108, the delivery shaft 106, components of the actuation assemblies
150, and when present--the outer shaft 104, can be coupled to the
handle 110. During delivery of the prosthetic valve 114, the handle
110 can be maneuvered by an operator (e.g., a clinician or a
surgeon) to axially advance or retract components of the delivery
apparatus 102, such as the nosecone shaft 108, the delivery shaft
106, and/or the outer shaft 104, through the patient's vasculature,
as well as to expand or contract the prosthetic valve 114, for
example by maneuvering the actuation assemblies 150, and to
disconnect the prosthetic valve 114 from the delivery apparatus
102, for example--by decoupling the actuators 151 from the actuator
assemblies 134 of the valve 114, in order to retract it once the
prosthetic valve is mounted in the implantation site.
[0250] The term "and/or" is inclusive here, meaning "and" as well
as "or". For example, "delivery shaft 106 and/or outer shaft 104"
encompasses, delivery shaft 106, outer shaft 104, and delivery
shaft 106 with outer shaft 104; and, such "delivery shaft 106
and/or outer shaft 104" may include other elements as well.
[0251] According to some embodiments, the handle 110 can include
one or more operating interfaces, such as steerable or rotatable
adjustment knobs, levers, sliders, buttons (not shown) and other
actuating mechanisms, which are operatively connected to different
components of the delivery apparatus 102 and configured to produce
axial movement of the delivery apparatus 102 in the proximal and
distal directions, as well as to expand or contract the prosthetic
valve 114 via various adjustment and activation mechanisms as will
be further described below.
[0252] According to some embodiments, the handle further comprises
one or more visual or auditory informative elements 112 configured
to provide visual or auditory information and/or feedback to a user
or operator of the delivery apparatus 102, such as a display 113a,
LED lights 113b, speakers (not shown) and the like.
[0253] FIG. 2A shows an example of a mechanically expandable
prosthetic valve 114.sup.a in an expanded state, according to some
embodiments. FIG. 2B shows the prosthetic valve 114.sup.a of FIG.
2A with actuation assemblies 150 coupled to the expansion and
locking assemblies 134. Soft components, such as leaflets or
skirts, are omitted from view in FIG. 2A to expose the expansion
and locking assemblies 134. The prosthetic valve 114 can comprise
an inflow end portion 118 defining an inflow end 119, and an
outflow end portion 116 defining an outflow end 117. In some
instances, the outflow end 117 is the distal end of the prosthetic
valve 114, and the inflow end 119 is the proximal end of the
prosthetic valve 114. Alternatively, depending for example on the
delivery approach of the valve, the outflow end can be the proximal
end of the prosthetic valve, and the inflow end can be the distal
end of the prosthetic valve.
[0254] The term "outflow", as used herein, refers to a region of
the prosthetic valve through which the blood flows through and out
of the valve 114, for example between the valve longitudinal axis
20 and the outflow end 117.
[0255] The term "inflow", as used herein, refers to a region of the
prosthetic valve through which the blood flows into the valve 114,
for example between inflow end 119 and the valve longitudinal axis
20.
[0256] The valve 114 comprises a frame 120 composed of
interconnected struts 121, and may be made of various suitable
materials, such as stainless steel, cobalt-chrome alloy (e.g. MP35N
alloy), or nickel titanium alloy such as Nitinol. According to some
embodiments, the struts 121, such as struts 121.sup.a shown in
FIGS. 2A-B, are arranged in a lattice-type pattern. In the
embodiment illustrated in FIGS. 2A-B, the struts 121.sup.a are
positioned diagonally, or offset at an angle relative to, and
radially offset from, the valve longitudinal axis 20, when the
valve 114.sup.a is in an expanded position. It will be clear that
the struts 121.sup.a can be offset by other angles than those shown
in FIGS. 2A-B, such as being oriented substantially parallel to the
valve longitudinal axis 20.
[0257] According to some embodiments, the struts 121 are pivotably
coupled to each other. In the example embodiment shown in FIGS.
2A-B, the end portions of the struts 121 are forming apices 125 at
the outflow end 117 and apices 126 at the inflow end 119. The
struts 121 can be coupled to each other at additional junctions 124
formed between the outflow apices 125 and the inflow apices 126.
The junctions 124 can be equally spaced apart from each other,
and/or from the apices 125, 126 along the length of each strut 121.
Frame 120, such as the frame 120.sup.a of a mechanically expandable
valve, may comprise openings or apertures at the regions of apices
125, 126 and junctions 124 of the struts 121. Respective hinges can
be included at locations where the apertures of struts 121 overlap
each other, via fasteners, such as rivets or pins, which extend
through the apertures. The hinges can allow the struts 121 to pivot
relative to one another as the frame 120 is radially expanded or
compressed.
[0258] In alternative embodiments, the struts are not coupled to
each other via respective hinges, but are otherwise pivotable or
bendable relative to each other, so as to permit frame expansion or
compression. For example, the frame (e.g., frame 120.sup.b
illustrated in FIG. 15) can be formed from a single piece of
material, such as a metal tube, via various processes such as, but
not limited to, laser cutting, electroforming, and/or physical
vapor deposition, while retaining the ability to collapse/expand
radially in the absence of hinges and like.
[0259] Strut portions 122 are defined between adjacent junctions
124, such as between two consecutive junctions 124 along the same
strut 121, or between a junction 124 and an apex 125, 126. The
frame 120 further comprises a plurality of cells 127, defined
between intersecting strut portions 122. The shape of each cell
127, and the angle between each intersecting strut portion 122
defining its borders, vary during expansion or compression of the
prosthetic valve 114.
[0260] The prosthetic valve 114 further comprises a leaflet
assembly 128 having one or more leaflets 129, e.g., three leaflets,
configured to regulate blood flow through the prosthetic valve 114
from the inflow end to the outflow end. While three leaflets 129
arranged to collapse in a tricuspid arrangement similar to the
native aortic valve, are shown in the example embodiment
illustrated in FIG. 2A, it will be clear that a prosthetic valve
114 can include any other number of leaflets 129, such as two
leaflets configured to collapse in a bicuspid arrangement similar
to the native mitral valve, or more than three leaflets, depending
upon the particular application. The leaflets 129 are made of a
flexible material, derived from biological materials (e.g., bovine
pericardium or pericardium from other sources), bio-compatible
synthetic materials, or other suitable materials as known in the
art and described, for example, in U.S. Pat. Nos. 6,730,118,
6,767,362 and 6,908,481, which are incorporated by reference
herein.
[0261] The leaflets 129 may be coupled to the frame 120 via
commissures 130, either directly or attached to other structural
elements connected to the frame 120 or embedded therein, such as
commissure posts. Further details regarding prosthetic valves,
including the manner in which leaflets may be mounted to their
frames, are described in U.S. Pat. Nos. 7,393,360, 7,510,575,
7,993,394 and 8,252,202, and U.S. Patent Application No.
62/614,299, all of which are incorporated herein by reference.
[0262] According to some embodiments, the prosthetic valve 114 may
further comprise at least one skirt or sealing member, such as the
inner skirt 132 shown in the exemplary embodiment illustrated in
FIG. 2A. The inner skirt 132 can be mounted on the inner surface of
the frame 120, configured to function, for example, as a sealing
member to prevent or decrease perivalvular leakage. The inner skirt
132 can further function as an anchoring region for the leaflets
129 to the frame 120, and/or function to protect the leaflets 129
against damage which may be caused by contact with the frame 120,
for example during valve crimping or during working cycles of the
prosthetic valve 114. Additionally, or alternatively, the
prosthetic valve 114 can comprise an outer skirt 133 (see, for
example, in FIG. 17B) mounted on the outer surface of the frame
120, configure to function, for example, as a sealing member
retained between the frame 120 and the surrounding tissue of the
native annulus against which the prosthetic valve 114 is mounted,
thereby reducing risk of paravalvular leakage past the prosthetic
valve 114. Any of the inner skirt 132 and/or outer skirt 133 can be
made of various suitable biocompatible materials, such as, but not
limited to, various synthetic materials (e.g., PET) or natural
tissue (e.g. pericardial tissue).
[0263] According to some embodiments, a mechanically expandable
valve 114.sup.a comprises a plurality of expansion and locking
assemblies 134, configured to facilitate expansion of the valve
114.sup.a, and in some instances, to lock the valve at an expanded
state, preventing unintentional recompression thereof, as will be
further elaborated below. Although FIGS. 2A-B illustrate three
expansion and locking assemblies 134, mounted to, and equally
spaced, around an inner surface of the frame 120.sup.a, it should
be clear that a different number of expansion and locking
assemblies 134 may be utilized, that the expansion and locking
assemblies 134 can be mounted to the frame 120.sup.a around its
outer surface, and that the circumferential spacing between
actuator assemblies 134 can be unequal.
[0264] FIGS. 3A, 3B and 3C show an exploded view in perspective, an
assembled view in perspective, and a cross-sectional side view,
respectively, of an expansion and locking assembly 134 according to
some embodiments. The expansion and locking assembly 134 may
include an outer member 136 defining an outer member lumen 139,
secured to a component of the valve 114.sup.a, such as the frame
120.sup.a, at a first location, and an inner member 144 secured to
a component of the valve 114.sup.a, such as the frame 120.sup.a, at
a second location, axially spaced from the first location.
[0265] The inner member 144 extends between an inner member
proximal end portion 145 and an inner member distal end portion
146. The inner member 144 comprises an inner member coupling
extension 149 extending from its distal end portion 158, which may
be formed as a pin extending radially outward from the distal end
portion 146, configured to be received within respective openings
or apertures of struts 121 intersecting at a non-apical junction
124 or an apex 125, 126. The inner member 144 may further comprise
a linear rack having a plurality of ratcheting teeth 148 along at
least a portion of its length. According to some embodiments, inner
member 144 further comprises a plurality of ratcheting teeth 148
along a portion of its outer surface.
[0266] The outer member 136 comprises an outer member proximal end
portion 137 defining a proximal opening of its lumen 139, and an
outer member distal end portion 138 defining a distal opening of
its lumen 139. The outer member 136 can further comprise an outer
member coupling extension 140 extending from its proximal end
portion 137, which may be formed as a pin extending radially
outward from the external surface of the proximal end portion 137,
configured to be received within respective openings or apertures
of struts 121 intersecting at a non-apical junction 124 or an apex
125, 126.
[0267] The outer member 136 can further comprise a spring biased
arm 142, attached to or extending from one sidewall of the outer
member 136, and having a tooth or pawl 143 at its opposite end,
biased inward toward the inner member 144 when disposed within the
outer member lumen 139.
[0268] At least one of the inner or outer member 144 or 136,
respectively, is axially movable relative to its counterpart. The
expansion and locking assembly 134 in the illustrated embodiment,
comprises a ratchet mechanism or a ratchet assembly, wherein the
pawl 143 is configured to engage with the teeth 148 of the inner
member 144. The spring-biased arm 142 can comprise an elongate body
terminating in a pawl 143 in the form of a locking tooth,
configured to engage the ratcheting teeth 148 of the inner member
144. The pawl 143 can have a shape that is complimentary to the
shape of the teeth 148, such that the pawl 143 allows sliding
movement of the inner member 144 in one direction relative to the
spring-biased arm 142 (proximal direction in the illustrated
embodiment) and resists sliding movement of the inner member 144 in
the opposite direction (distal direction in the illustrated
embodiment) when the pawl 143 is in engagement with one of the
teeth 148.
[0269] Referring again to FIG. 3C, the arm 142 can be biased
inwardly such that the pawl 143 is resiliently retained in a
position engaging one of the teeth 148 of the inner member 144
(which can be referred to as the engaged position of the pawl 143).
The spring-biased arm 142 can be formed of a flexible or resilient
portion of the outer member 136 that extends over and contacts, via
its pawl 143, an opposing side of the outer surface of the inner
member 144. According to some embodiments, the spring-biased arm
142 can be in the form of a leaf spring that can be integrally
formed with the outer member 136 or separately formed and
subsequently connected to the outer member 136. The spring-biased
arm 142 is configured to apply a biasing force against the outer
surface of the inner member 144, so as to ensure that under normal
operation, the pawl 143 stays engaged with the ratcheting teeth 148
of the inner member 144.
[0270] A mechanically expandable prosthetic valve 114.sup.a may be
releasably attachable to at least one actuation assembly 150, and
preferably a plurality of actuation assemblies 150, matching the
number of expansion and locking assemblies 134. In some
embodiments, the prosthetic valve 114 comprises three expansion and
locking assemblies 134, and the delivery apparatus 102.sup.a
comprises three actuation assemblies 150. The actuator 151 and the
sleeve 153 can be movable longitudinally relative to each other in
a telescoping manner to radially expand and contract the frame
120.sup.a, as further described in U.S. Publication Nos.
2018/0153689, 2018/0153689 and 2018/0325665, which are incorporated
herein by reference. The actuators 151 can be, for example, wires,
cables, rods, or tubes. The sleeves 153 can be, for example, tubes
or sheaths having sufficient rigidity such that they can apply a
distally directed force to the frame 120.sup.a or the outer member
136 without bending or buckling.
[0271] The inner member proximal end portion 145 further comprises
an inner member threaded bore 147, configured to receive and
threadedly engage with a threaded portion of a distal end portion
152 (shown for example in FIG. 4C) of a corresponding actuator 152.
FIG. 2B shows a view in perspective of a valve 114.sup.a in an
expanded state, having its expansion and locking assemblies 134
connected to actuators 151 (hidden from view within the sleeves
153) of a delivery apparatus 102.sup.a. When actuators 151 are
threaded into the inner members 144, axial movement of the
actuators 151 causes axial movement of the inner members 144 in the
same direction.
[0272] According to some embodiments, the actuation assemblies 150
are configured to releasably couple to the prosthetic valve
114.sup.a, and to move the prosthetic valve 114.sup.a between the
radially compressed and the radially expanded configurations. FIGS.
4A-4C illustrate a non-binding configuration representing actuation
of the expansion and locking assemblies 134 via the actuation
assemblies 150 to expand the prosthetic valve 114.sup.a from a
radially compressed configuration to a radially expanded
configuration.
[0273] FIG. 4A shows an expansion and locking assembly 134, having
an outer member 136, secured to the frame 120.sup.a at a first
location, and an inner member 144 secured to the frame 120.sup.a at
a second location. According to some embodiments, the first
location can be positioned at or adjacent to the outflow end
portion 116, and the second location can be positioned at or
adjacent to the inflow end portion 118. In the illustrated
embodiment, the outer member 136 is secured to a proximal-most
non-apical junction 124a which is distal to the outflow apices 125
or the outflow end 117, via outer member coupling extension 140,
and the inner member 144 is secured to a distal-most non-apical
junction 124c which is proximal to the inflow apices 126 or the
inflow end 119, via inner member coupling extension 149. A proximal
portion of the inner member 144 extends, through the distal opening
of the outer member distal end 138, into the outer member lumen
139.
[0274] It is to be understood that while the illustrated
embodiments are for an expansion and locking assembly 134 secured
to a proximal-most non-apical junction 124a serving as the first
location, and to a distal-most non-apical junction 124c serving as
the second location, in other implementations, the expansion and
locking assembly 134 can be secured to other junctions, including
apices of the valve. For example, the expansion and locking
assembly can be secured to an outflow apex 125 via the outer member
coupling extension 140, serving as the first location, and to an
opposing inflow apex 126 along the same column of cells, via the
inner member coupling extension 149, serving as the second
location.
[0275] The expansion and locking assembly 134 is shown in FIG. 4A
in a radially compressed state of the valve 114.sup.a, wherein the
outflow and inflow apices 125 and 126, respectively, are relatively
distanced apart from each other along the axial direction, and the
inner member proximal end portion 145 is positioned distal to the
outer member proximal end portion 137.
[0276] As further shown in FIG. 4A, the actuator distal end portion
152 is threadedly engaged with the inner member threaded bore 147.
According to some embodiments, as shown in FIGS. 4A-4C, the
actuator distal end portion 152 includes external threads,
configured to engage with internal threads of the inner member
threaded bore 147. According to alternative embodiments, an inner
member may include a proximal extension provided with external
threads, configured to be received in and engage with internal
threads of a distal bore formed within the actuator (embodiments
not shown).
[0277] The sleeve 153 surrounds the actuator 151 and may be
connected to the handle 110.sup.a of a delivery apparatus
102.sup.a. The sleeve 153 and the outer member 136 are sized such
that the distal lip 154 of the sleeve 153 can abut or engage the
outer member proximal end 137, such that the outer member 136 is
prevented from moving proximally beyond the sleeve 153.
[0278] In order to radially expand the frame 120.sup.a, and
therefore the valve 114.sup.a, the sleeve 153 can be held firmly
against the outer member 136. The actuator 151 can then be pulled
in a proximally oriented direction 14, as shown in FIG. 4B. Because
the sleeve 153 is being held against the outer member 136, which is
connected to the frame 120.sup.a at the first location, the outflow
end 117 of the frame 120.sup.a is prevented from moving relative to
the sleeve 153. As such, movement of the actuator 151 in a
proximally oriented direction 14 can cause movement of the inner
member 144 in the same direction, thereby causing the frame
120.sup.a to foreshorten axially and expand radially.
[0279] More specifically, as shown for example in FIG. 4B, the
inner member coupling extension 149 extends through apertures in
two struts 121.sup.a interconnected at a distal non-apical junction
124c, while the outer member coupling extension 140 extends through
aperture in two struts 121.sup.a interconnected at a proximal
non-apical junction 124a. As such, when the inner member 144 is
moved axially, for example in a proximally oriented direction 14,
within the outer member lumen 139, the inner member coupling
extension 149 moves along with the inner member 144, thereby
causing the portion to which the inner member coupling extension
149 is attached to move axially as well, which in turn causes the
frame 120.sup.a to foreshorten axially and expand radially.
[0280] The struts 121.sup.a to which the inner member coupling
extension 149 is connected are free to pivot relative to the
coupling extension 149 and to one another as the frame 120.sup.a is
expanded or compressed. In this manner, the inner member coupling
extension 149 serves as a fastener that forms a pivotable
connection between those struts 121.sup.a. Similarly, struts
121.sup.a to which the outer member coupling extension 140 is
connected are also free to pivot relative to the coupling extension
140 and to one another as the frame 120.sup.a is expanded or
compressed. In this manner, the outer coupling fastening extension
140 also serves as a fastener that forms a pivotable connection
between those struts 121.sup.a.
[0281] As mentioned above, when the pawl 143 of the spring biased
arm 142 is engaged with the ratcheting teeth 148, the inner member
144 can move in one axial direction, such as the proximally
oriented direction 14, but cannot move in the opposite axial
direction. This ensures that while the pawl 143 is engaged with the
ratcheting teeth 148, the frame 120.sup.a can radially expand but
cannot be radially compressed. Thus, after the prosthetic valve
114.sup.a is implanted in the patient, the frame 120.sup.a can be
expanded to a desired diameter by pulling the actuator 151. In this
manner, the actuation mechanism also serves as a locking mechanism
of the prosthetic valve 114.sup.a.
[0282] Once the desired diameter of the prosthetic valve 114.sup.a
is reached, the actuator 151 may be rotated, for example in
rotation direction 16, to unscrew the actuator 151 from the inner
member 144, as shown in FIG. 4C. This rotation serves to disengage
the distal threaded portion 152 of the actuator 151 from the inner
member threaded bore 147, enabling the actuation assemblies 150 to
be pulled away, and retracted, together with the delivery apparatus
102.sup.a, from the patient's body, leaving the prosthetic valve
114.sup.a implanted in the patient. The patient's native anatomy,
such as the native aortic annulus in the case of transcatheter
aortic valve implantation, may exert radial forces against the
prosthetic valve 114.sup.a that would strive to compress it.
However, the engagement between the pawl 143 of the spring biased
arm 142 and the ratcheting teeth 148 of the inner member 144
prevents such forces from compressing the frame 120.sup.a, thereby
ensuring that the frame 120.sup.a remains locked in the desired
radially expanded state.
[0283] Thus, the prosthetic valve 114.sup.a is radially expandable
from the radially compressed state shown in FIG. 4A to the radially
expanded state shown in FIG. 4B upon actuating the expansion and
locking assemblies 134, wherein such actuation includes
approximating the second locations to the first locations of the
valve 114.sup.a. The prosthetic valve 114.sup.a is further
releasable from the delivery apparatus 102.sup.a by decoupling each
of the actuation assemblies 150 from each of the corresponding
expansion and locking assemblies 134 that were attached
thereto.
[0284] While the frame 120.sup.a is shown above to expand radially
outward by axially moving the inner member 144 in a proximally
oriented direction 14, relative to the outer member 136, it will be
understood that similar frame expansion may be achieved by axially
pushing an outer member 136 in a distally oriented direction,
relative to an inner member 144.
[0285] While a threaded engagement is illustrated and described in
the above embodiments, serving as an optional reversible-attachment
mechanism between the actuation assemblies 150 and the inner
members 144, it is to be understood that in alternative
implementations, other reversible attachment mechanisms may be
utilized, configured to enable the inner member 144 to be pulled or
pushed by the actuation assemblies 150, while enabling
disconnection there-between in any suitable manner, so as to allow
retraction of the delivery apparatus from the patient's body at the
end of the implantation procedure. For example, the distal end
portion of the actuator can include a magnet, and the inner member
bore can include a correspondingly magnetic material into which the
distal end portion of the actuator can extend.
[0286] According to some embodiments, the handle 110 can comprise
control mechanisms which may include steerable or rotatable knobs,
levers, buttons and such, which are manually controllable by an
operator to produce axial and/or rotatable movement of different
components of the delivery apparatus 102. For example, the handle
110.sup.a may comprise one or more manual control knobs, such as a
manually rotatable control knob that is effective to pull the
actuator 151 when rotated by the operator.
[0287] According to other embodiments, control mechanisms in handle
110 and/or other components of the delivery apparatus 102 can be
electrically, pneumatically and/or hydraulically controlled.
According to some embodiments, the handle 110 can house one or more
electric motors which can be actuated by an operator, such as by
pressing a button or switch on the handle 110, to produce movement
of components of the delivery apparatus 102. For example, the
handle 110.sup.a may include one or more motors operable to produce
linear movement of components of the actuation assemblies 150,
and/or one or more motors operable to produce rotational movement
of the actuators 151 to disconnect the actuator distal end portion
152 from the actuation inner member threaded bore 147. According to
some embodiments, one or more manual or electric control mechanism
is configured to produce simultaneous linear and/or rotational
movement of all of the actuators 151.
[0288] While a specific actuation mechanism is described above,
utilizing a ratcheting mechanism between the inner and the outer
members of the expansion and locking assemblies 134, other
mechanisms may be employed to promote relative movement between
inner and outer members of expansion and locking assemblies, for
example via threaded or other engagement mechanisms. Further
details regarding the structure and operation of mechanically
expandable valves and delivery system thereof are described in U.S.
Pat. No. 9,827,093, U.S. Patent Application Publication Nos.
2019/0060057, 2018/0153689 and 2018/0344456, and U.S. Patent
Application Nos. 62/870,372 and 62/776,348, all of which are
incorporated herein by reference.
[0289] Prior to implantation, the prosthetic valve 114 can be
crimped onto the delivery apparatus 102. In some embodiments, this
step can include covering at least a portion of the radially
compressed valve 114 by the outer shaft 104 or by an external
capsule (not shown). Once delivered to the site of implantation,
such as a native annulus, the valve 114 can be radially expanded
within the annulus, for example, by actuating the expansion and
locking assemblies 134 described herein above in the case of
mechanically expandable valves 114.sup.a. However, during such
implantation procedures, it may become desirable to re-compress the
prosthetic valve 114.sup.a in situ in order to reposition it. Valve
recompression may be achievable, for example, if the mechanically
expandable valve 114.sup.a has not yet reached a locked state, for
example by providing a sufficient smooth length (i.e., devoid of
ratcheting teeth 148) along the inner member 144, so as to allow
axial movement along a specific distance prior to pawl 143
engagement with the teeth 148. Alternatively or additionally, the
delivery assembly 100.sup.a can further include release members
(not shown), configured to release the pawl 143 from the teeth 148
to allow reversible movement that will enable valve
compression.
[0290] According to some embodiments, the handle 110 includes a
control unit 111.sup.a configured to receive measurement signals
from the at least one communication channel 160, and produce a
measure indicative of valve expansion diameter in real time.
Control unit 111.sup.a can include a central processing unit (CPU),
a microprocessor, a microcomputer, a programmable logic controller,
an application-specific integrated circuit (ASIC) and/or a
field-programmable gate array (FPGA), without limitation. The
control unit 111.sup.a may be provided as an electrical or an
electro-optical circuitry.
[0291] According to some embodiments, the delivery apparatus 102
further comprises a flex sensing assembly 156 in communication with
control unit 111.sup.a. Responsive to an output of flex sensing
assembly 156, control unit 111.sup.a is configured to measure
angular displacement of at least one strut 121 of a prosthetic
valve 114. More specifically, the flex sensing assembly 156
comprises at least one flex sensor coupled to at least one strut
121, from which an angle, such as an opening angle of the valve
114, can be derived. The opening angle may be correlated to the
valve expansion diameter, so as to provide a real-time indication
of the valve diameter.
[0292] The terms coupled, engaged and attached, as used herein, are
interchangeable. Similarly, the term decoupled, disengaged and
detached, as used herein, are interchangeable.
[0293] Reference is now made to FIGS. 5A-5C, showing different
optional stages of utilizing a delivery assembly 100 equipped with
a flex sensing assembly 156. The leaflet assembly 128 and skirt 132
are omitted from FIGS. 5A-14E for purposes of clarity. FIG. 5A
shows an enlarged view of a distal portion of the delivery assembly
100, carrying a prosthetic valve 114 retained in a compressed or
crimped state within a distal portion of the outer shaft 104 during
delivery to the implantation site. As described above, the distal
portion of the outer shaft 104 can serve as a delivery capsule that
covers the crimped prosthetic valve 114. Upon reaching the desired
site of implantation, the outer shaft 104 can be retracted to
expose the prosthetic valve 114. FIG. 5A shows partial retraction
of the outer shaft 104, exposing a distal portion of the valve 114,
such as the inflow end portion 118.
[0294] FIG. 5B shows the prosthetic valve 114 exposed (i.e., no
longer covered by the outer shaft 104). Certain prosthetic valves
114, such as certain mechanically expandable valves 114.sup.a as
described above in conjunction with FIGS. 1-4C, may be provided
with internal resiliency promoting partial expansion thereof when
extended out of a capsule or outer shaft 104. FIG. 5C shows the
valve 114 further expanded, for example to a partially-expanded or
a fully expanded diameter thereof.
[0295] According to some embodiments, the flex sensing assembly 156
comprises at least one flex sensor 170. The flex sensor 170 is
defined between a flex sensor proximal end 172 and a flex sensor
distal end 173. An output of at least one flex sensor 170 is
configured to represent the flex of at least one flex sensor 170,
including an electrical and/or optical output. Particularly,
according to some embodiments, and as known to those skilled in the
art, at least one flex sensor 170 can be electrical, such that the
electrical resistance thereof varies responsive to the flex of at
least one flex sensor 170. For example, control unit 111.sup.a can
generate a current that flows through at least one flex sensor 170,
the voltage at the output of at least one flex sensor 170 thus
representing the flex thereof. Alternatively, control unit
111.sup.a can apply a voltage across at least one flex sensor 170,
the current at the output of at least one flex sensor 170 thus
representing the flex thereof. Additionally, or alternately, at
least one flex sensor 170 can be optical, such that the amount of
light transmitted between proximal end 172 and distal end 173
varies responsive to the flex of at least one flex sensor 170. For
example, a light source can be provided at distal end 173, the
amount of light at the output of at least one flex sensor 170 (e.g.
at proximal end 172) thus representing the flex thereof.
[0296] The flex sensing assembly 156 may further comprise at least
one communication channel 160, extending distally from the handle
110 to a communication channel distal end 161, and coupled to
control unit 111.sup.a. The term "communication channel", as used
herein, means a physical path allowing communication therethrough.
According to some embodiments, the communication channel is
configured to allow: electrical communication via a conductive
material, such as a wire; and/or optical communication, e.g. via an
optical fiber. The communication channel distal end 161 may be
coupled to a respective flex sensor proximal end 172 at an
interface 164. Each communication channel 160 may extend into the
handle 110. When coupled to the flex sensor 170 at interface 164,
the communication channel 160 is configured to conduct the signals
(either an electric and/or an optic signals) from the output of
flex sensor 170 towards control unit 111.sup.a. In some instances,
the communication channel 160 may be integrally formed with the
flex sensor 170. For example, the communication channel 160 may be
formed as a continuous extension of the flex sensor 170.
Alternatively, the communication channel 160 and the flex sensor
170 may be provided as separate components attached to each other
at interface 164. According to some embodiments, the communication
channel 160 is detachably coupled to the flex sensor 170.
[0297] According to some embodiments, the flex sensing assembly 156
further comprises a sensor shaft 158, extending distally from the
handle 110 to a sensor shaft distal end 159, wherein at least a
portion of the communication channel 160 extends through a lumen of
the sensor shaft 158. According to some embodiments, the
communication channel 160 is axially movable within the lumen of
the sensor shaft 158.
[0298] In some configurations, the interface 164 may be positioned
within the lumen of the sensor shaft 158, such that a proximal
portion of the flex sensor 170 is disposed within the sensor shaft
158, while the remainder of the flex sensor 170 extends out of the
sensor shaft 158. In some configurations, the interface 164 may be
positioned distal to the sensor shaft distal end 159, such that a
distal portion of the communication channel 160, and the entire
length of the flex sensor 170, extend out of the sensor shaft
158.
[0299] According to some embodiments, the at least one flex sensor
170 is coupled to at least one strut 121, for example to a strut
portion 122, to measure angular movement and/or angular orientation
thereof during valve expansion or compression. The angular movement
and/or angular orientation of the at least one strut 121, and more
specifically, the at least one strut portion 122, may be measured
relative to an axis, such as the valve longitudinal axis 20 or the
sensor shaft axis 22, and/or relative to another structural
component of the valve 114, such as another intersecting strut 121
or strut portion 122, an actuator outer member 136, a commissure
post (e.g., an outer member 136 or any other commissure post), a
vertical portion of the frame, and the like.
[0300] The exemplary embodiment shown in FIGS. 5B-5C illustrates a
flex sensing assembly 156 comprising two flex sensors 170, coupled
to two intersecting struts 121, and more specifically, to two
intersecting strut portions 122. While this configuration may be
advantageous for some applications, it will be understood that any
other number of flex sensors 170 is contemplated, including a
single flex sensor or more than two flex sensors.
[0301] According to some embodiments, as shown, a first flex sensor
170a and a second flex sensor 170b are coupled to a first strut
portion 122a of a first strut 121a and a second strut portion 122b
of a second strut 121b, respectively, intersecting at a junction
124. In some applications, the intersection junction may be an
outflow apex 125.
[0302] According to some embodiments, a first communication channel
160a is coupled to the first flex sensor 170a, and a second
communication channel 160b is coupled to the second flex sensor
170b. According to some embodiments, the plurality of communication
channels 160a may extend through the lumen of a single sensor shaft
158. In alternative embodiments, the flex sensing assembly 156
comprises a plurality of sensor shafts 158, such that each
communication channel 160 may extend through the lumen of a
respective, different, sensor shaft 158.
[0303] A sensor shaft axis 22 is defined as a longitudinal axis
orthogonal to the plane of the opening at the sensor shaft distal
end 159. As shown in FIG. 5C, when the valve 114 expands, a first
angle .alpha..sub.1 may be defined between the first strut portion
122a and the sensor shaft axis 22, and a second first angle
.alpha..sub.2 may be defined between the second strut portion 122b
and the sensor shaft axis 22, such that the sum of the first and
second angles .alpha..sub.1 and .alpha..sub.2, respectively,
results in an opening angle .beta. defined between the two
intersecting struts 121a and 121b at the intersection junction
124.
[0304] According to some embodiments, each flex sensor 170
comprises a bending portion 180 coupled to the respective strut 121
(e.g., to the respective strut portion 122), and a non-bending
portion 181 extending proximal to the intersection junction 124,
wherein each bending portion 180 may bend, along with the strut 121
(e.g., along the strut portion 122), relative to the non-bending
portion 181.
[0305] According to some embodiments, the first non-bending portion
181a and the second non-bending portion 181b are aligned with each
other, such that they may be substantially disposed in parallel
with each other.
[0306] One element is termed to be substantially parallel with
another element if both elements are angled at an angle of no more
than 5 degrees relative to each other.
[0307] Typically, the sensor shaft axis 22 is collinear with the
longitudinal axes of the first non-bending portions 181. According
to some embodiments, the first angle .alpha..sub.1 may be defined
between a longitudinal axis of the first bending portion 180a and a
longitudinal axis of the first non-bending portion 181a, and the
second first angle .alpha..sub.2 may be defined between a
longitudinal axis of the second bending portion 180b and a
longitudinal axis of the second non-bending portion 181b, such that
the sum of the first and second angles .alpha..sub.1 and
.alpha..sub.2, respectively, results in an opening angle .beta.
defined between the longitudinal axis of the first bending portion
180a and the longitudinal axis of the second bending portion
180.
[0308] According to some embodiments, the sensor shaft distal end
159 is positioned adjacent to the junction 124, and the interface
164 is disposed within the lumen of the sensor shaft 158, such that
upon valve expansion, the sensor shaft distal end 159 acts as a
fulcrum for the bending portions 180a, 180b, defining the
non-bending portions 181a, 181b between the interfaces 164a, 164b
and the sensor shaft distal ends 159a, 159b, respectively.
[0309] According to some embodiments, each flex sensor 170 is
coupled to a respective strut 121 via at least one coupling member
188. The at least one coupling member 188 can be in the form of a
suture, a band, a sleeve, a snap-fit member, glue, and the like.
According to some embodiments, at least one coupling member 188 is
a non-affixing coupling member, configured to couple the flex
sensor 170 to the strut 121 in a manner that prevents spontaneous
displacement of the flex sensor 170, yet allows axial movement or
sliding of the flex sensor 170 over and relative to the strut 121,
for example during valve expansion or compression, or during
application of a pulling force to retract the flex sensor 170 from
the valve 114. According to some embodiments, at least one coupling
member 188 is an affixing coupling member, configured to affix the
flex sensor 170 to the strut 121, for example by gluing or
welding.
[0310] According to some embodiments, the at least one flex sensor
170 is coupled to a respective strut 121 via a plurality of
coupling members 188. According to some embodiments, the at least
one flex sensor 170 is coupled to a respective strut 121 via more
than one type of a coupling member 188. According to some
embodiments, the at least one flex sensor 170 is coupled to a
respective strut 121 via a plurality of coupling members 188
comprising at least one affixing coupling member and at least one
non-affixing coupling member. For example, a flex sensor 170 can be
affixed to the strut 121 by being glued, welded, riveted and the
like, at a proximal point of attachment--such as in the vicinity of
the intersection junction 124, and one or more non-affixing
coupling members, such as suture loops, tubes, sleeves, bands,
rails and the like, distal to the affixing coupling member. In such
an example, the flex sensor 170 may be affixed to the strut 121 at
the affixation point, while the remained of the flex sensor 170 may
slide over the strut 121 as the opening angle changes, so as to
prevent the flex sensor 170 from being over-tensioned during valve
expansion.
[0311] According to some embodiments, the at least one flex sensor
170 is coupled to a respective strut 121 via one or more coupling
members 188 that include only non-affixing coupling members. For
example, the flex sensor 170 may be coupled to the strut 121 via a
plurality of spaced apart suture loops or bands, tightly looped
around the flex sensor 170 and the strut 121 so as to prevent
spontaneous movement there-between. In such an example, the flex
sensor 170 may slide within the coupling members 188 relative to
the strut 121, during valve expansion (or contraction) or
application of a retraction force, which exceed the frictional
forces applied by the coupling members 188 on the flex sensor
170.
[0312] According to some embodiments, the at least one flex sensor
170 is coupled to a respective strut 121 via more than one type of
non-affixing coupling members. According to some embodiments, a
flex sensor 170 is coupled to the strut 121 via at least one first
type of a non-affixing coupling member, and at least one second
type of non-affixing coupling member, distal to the first type of
non-affixing coupling member, wherein the first type of
non-affixing member is configured to release the flex sensor 170
from, or allow movement of the flex sensor 170 relative to, the
strut 121, upon application of a retraction force higher than that
required to allow such relative movement within or along the second
type of non-affixing coupling members.
[0313] For example, a flex sensor 170 can be coupled to the strut
121 by a first type of a non-affixing coupling member in the form
of a releasable snap-fit member, at a proximal point of
attachment--such as in the vicinity of the intersection junction
124, and one or more second type of non-affixing coupling members,
such as suture loops, tubes, sleeves, bands, rails and the like,
distal to the first type of a non-affixing coupling member. In such
an example, the flex sensor 170 may be immovable relative to the
strut 121 at the snap-fit coupling member, while the remainder of
the flex sensor 170 may slide over the strut 121 as the opening
angle changes. However, once expansion is complete and removal of
the flex sensor 170 from the valve 114 is desired, the handle 110
can be further maneuvered to retract the sensor 170 at a higher
force magnitude than the force applied during valve expansion,
wherein the pull force is sufficient to detach the snap-fit member
188 so as to allow the flex sensor 170 to be released from the
strut 121.
[0314] According to some embodiments, the prosthetic valve 114 is
further releasable from the delivery apparatus 102 by decoupling at
least a portion of each flex sensor assembly 156 from the
prosthetic valve 114. In some applications, decoupling at least a
portion of each flex sensor assembly 156 refers to at least the
communication channels 160 being retractable from the prosthetic
valve, either with the flex sensors 170 remaining coupled thereto,
or without the flex sensors 170 which may be decoupled
therefrom.
[0315] According to some embodiments, the valve 114 is releasable
from the delivery apparatus 102 by decoupling each communication
channel 160 from the corresponding flex sensor 170 it was attached
to, while the flex sensors 170 may remain attached to the
respective struts 121. According to some embodiments, the valve 114
is further releasable from the delivery apparatus 102 by decoupling
each flex sensor 170 from the strut 121 it was coupled to, for
example, by pulling the flex sensors 170 at a force sufficient to
overcome friction forces applied thereto by the respective coupling
members 188.
[0316] The control unit 111.sup.a can be configured to continuously
calculate the diameter of the prosthetic valve 114, responsive to
the output of at least one flex sensor 170. According to some
embodiments, the control unit 111.sup.a is operatively couple to a
visual interface 112, such as a display 113a and/or LED lights
113b. The display 113a may comprise a digital screen, which may
present numerical values indicative of the valve current diameter,
as well as other icons, textual messages or graphical symbols.
Additionally or alternatively, a visual interface 112 may comprise
LED lights 113b, lamps or other visual elements, configured to
provide the user with a visual indication of the current valve
diameter. According to some embodiments, the control unit 111.sup.a
is configured to display the diameter of the prosthetic valve 114
on the visual interface 112 in real-time, as the prosthetic valve
114 is expanded and/or compressed during an implantation
procedure.
[0317] According to some embodiments, the control unit 111.sup.a
further comprises a memory. According to some embodiments, selected
data, such as raw signal data or calculated data, may be stored in
the memory. According to some embodiments, the control unit
111.sup.a is configured to log data during the implantation
procedure in the memory. According to some embodiments, the control
unit 111.sup.a is configured to transmit to a remote device, logged
data from the memory, and/or real-time data.
[0318] According to some embodiments, the flex sensor 170 may be
operatively coupled, for example via communication channel 160, to
the control unit 111.sup.a, and configured such that control unit
111.sup.a can read the output of flex sensor 170. Responsive to the
output of flex sensor 170, control unit 111.sup.a derives measures
such as magnitude or degree of flex. As described above, control
unit 111.sup.a performs and/or receives electrical and/or optical
measurements from flex sensor 170. These measurements can be used
as a surrogate index in order to estimate valve expansion diameter
or changes in diameter.
[0319] According to some embodiments, the control unit 111.sup.a is
configured to provide an alert to an operator (e.g., a clinician)
in the event of valve over-expansion within a native annulus. For
example, an opening angle .beta. can be derived from the extent of
the bend measured by the at least one flex sensor 170. According to
some embodiments, the opening angle .beta. is derived from flex
measurements from at least two flex sensor 170, optionally coupled
to two intersecting struts 121. The opening angle .beta. can be
correlated with a valve expansion diameter, and compared against
one or more threshold values. Depending on the result (e.g., if a
relevant threshold is exceeded), a state of valve over-expansion
can be determined. The alert may be an audible alert, a visual
alert, a tactile alert, or any combination thereof.
[0320] The terms bend and flex, as used herein, are
interchangeable.
[0321] According to some embodiments, known relationships between
different opening angles and valve expansion diameters are stored
in the memory of the control unit 111.sup.a. The numerical value of
the expansion diameter of the valve 114 may be derived from the
opening angle .beta., based on any of: mathematical formulas,
graphs, and/or tables, which may be stored in the memory. According
to some embodiments, a visual indication of the expansion diameter
may be displayed on a digital screen 113a, and may include: a
numerical value, an icon or other graphical symbol, a textual
message, or any combination thereof.
[0322] According to some embodiments, the control unit 111.sup.a
may be further configured to control the actuation assemblies 150
and/or the re-compression assembly 180, to expand and/or contract
the prosthetic valve 114.sup.a, according to pre-programmed
expansion/contraction algorithms. In one example, the handle
110.sup.a may be maneuvered to gradually expand the valve 114.sup.a
(for example, by pulling the actuators 151, which are attached at
this stage to the expansion and locking assemblies 134). During the
expansion of the valve 114, the flex sensing assembly 156 provides
flex signals to the control unit 111.sup.a, from which the valve
diameter may be derived. The data may be interpreted by the control
unit 111.sup.a, and may be visually displayed via a display 113a or
LED lights 113b comprised in the handle 110. The displayed
interpreted data, which can include real-time valve expansion
diameter, may assist the clinician in decision making regarding the
next required steps of the implantation procedure, or serve as
input data for algorithms executed by the control unit 111.sup.a to
automatically expand or adjust valve diameter.
[0323] Once the valve 114 is sufficiently expanded, the handle 110
can be further maneuvered to release the actuation assemblies 150
from the valve 114.sup.a, for example as elaborated in conjunction
with FIGS. 4A-4C, and/or to decouple at least a portion of the flex
sensing assembly 156 from the valve 114.
[0324] According to some embodiments, the control unit 111.sup.a,
and/or the visual interface 112, may be provided as distinct
components separated from the delivery apparatus 102, which can be
operatively connected thereto, for example using wires/cables, or
via wireless communication protocols. According to additional
embodiments, the control unit, and/or the visual interface 112, are
integrated within the handle 110. For example, a processor and
other electrical components of control unit 111.sup.a can be
located within the handle 110, and the visual interface 112 may be
located on an exterior surface of the handle 110, such that it can
be viewed by a clinician during the implantation procedure.
[0325] In the exemplary embodiment shown in FIG. 5C, the first
angle .alpha..sub.1 is derived from the bend measurement signals of
the first flex sensor 170a relative to the sensor shaft axis 22,
and the second angle .alpha..sub.2 is derived from the bend
measurement signals of the second flex sensor 170b relative to the
sensor shaft axis 22, wherein the sensor shaft axis 22 is shown to
be oriented substantially parallel to the valve longitudinal axis
20. If the sensor shaft axis 22 indeed remains substantially
parallel to the valve longitudinal axis 20 during valve expansion,
it may be argued that one flex sensor 170 may be sufficient to
derive an opening angle .beta.. For example, a single flex sensor,
such as the first flex sensor 170a, may be used to measure the
first angle .alpha..sub.1, which should be identical to the second
angle .alpha..sub.2 in such cases, thus enabling derivation of the
opening angle .beta. from a simple multiplication of the first
angle .alpha..sub.1.
[0326] In cases wherein the orientation of the sensor shaft axis 22
cannot be guaranteed to be predictable or constant throughout valve
expansion, it may be required for the flex sensing assembly 156 to
include more than one flex sensor 170a, to ensure accurate
derivation of the opening angle .beta.. FIG. 6A shows an exemplary
embodiment of a flex sensing assembly 156 equipped with a single
flex sensor 170a, coupled to a single strut 121a. The nosecone 109
and nosecone shaft 108 are omitted from view in FIGS. 6A-14E for
the sake of clarity. As shown in FIG. 6A, the sensor shaft axis 22
may be oriented at a non-parallel orientation (e.g., angled)
relative to the valve longitudinal axis 20, or any axis parallel to
valve longitudinal axis 20. If the orientation of the sensor shaft
axis 22 is known, and remains constant throughout valve expansion,
a single flex sensor 170a may still suffice for derivation of the
opening angle .beta. from a single angle .alpha..sub.1 relative to
the sensor shaft axis 22. However, if the sensor shaft axis 22
cannot be determined, and more specifically, if the orientation of
the sensor shaft 158, and hence, the orientation of the sensor
shaft axis 22, is subject to changes during the valve implantation
procedure, the opening angle .beta. may not be accurately derived
only from the single angle .alpha..sub.1.
[0327] FIG. 6B shows an exemplary configuration of a flex sensing
assembly 156 equipped with first flex sensor 170a, coupled to the
first strut 121a, and a second flex sensor 170b, coupled to the
intersecting second strut 121b, wherein the sensor shaft axis 22
may be oriented at a non-parallel orientation (e.g., angled)
relative to the valve longitudinal axis 20. In this configuration,
the opening angle .beta. may be derived from the sum of non-equal
angles .alpha..sub.1 and .alpha..sub.2 at any measurement time
instance, regardless of the relative orientation of the sensor
shaft 158 and the sensor shaft axis 22. This configuration,
advantageously, enables continuous derivation of the opening angle
.beta., without requiring affixation of the sensor shaft 158 to a
predetermined angular orientation.
[0328] FIG. 7 shows an exemplary embodiment of a flex sensing
assembly 156 equipped with a single flex sensor 170, coupled to two
intersecting strut 121a and 121c. As shown, the flex sensor 170 may
include a first (e.g., proximal) bending portion 180a, coupled to a
first strut 121a, for example extending along a first strut portion
122a up to an intersection junction 124c, and a second (e.g.,
distal) bending portion 180c, coupled to a second strut 121c, for
example extending along a second strut portion 122c from the
intersection junction 124c. An opening angle .gamma. is defined
between the first strut 121a and the second strut 121c at the
common intersection junction 124c. During expansion, the flex
sensor 170 may assume a V-shaped configuration, having the apex of
the V-shape at the intersection junction 124c. The opening angle
.gamma. can be derived from the bending of the second bending
portion 180c relative to the first bending portion 180a, and
correlated in turn with valve expansion diameter.
[0329] While the opening angle y shown in FIG. 7 is measured
between different intersecting struts 121 that the opening angle
.beta. of FIG. 6B, for example, it will be clear that any angle
measured between a strut 121 and another structure of the valve 114
intersecting therewith, such as another intersecting strut 121, may
serve as the valve opening angle that can be correlated with valve
expansion diameter. In the case of diamond-shaped cells 127, as
illustrated in FIG. 7 for example, each angle at any junction 124
of the cell 127 may be used to easily derive any other angle of the
cell 127. As such, any embodiment of the current invention,
referring to an opening angle .beta., is similarly applicable to
any other opening angle of the valve 114, such as opening angle
.gamma..
[0330] According to some embodiments, the non-bending portion 181
is coupled to an expansion and locking assembly 134 or any
component thereof (e.g., an actuator outer member 136), while the
bending portion 180 is coupled to a strut 121.sup.a, which may
pivot relative to the expansion and locking assembly 134 during
valve expansion or contraction. Coupling of the non-bending portion
181 to the expansion and locking assembly 134 may be realized as
direct coupling or as indirect coupling. For example, direct
coupling may be direct attachment of the non-bending portion 181 to
an outer member 136, for example by gluing, welding, riveting, or
various types of coupling member 188. In another example, indirect
coupling may be realized by attachment of a sensor shaft 158 (e.g.,
a distal portion thereof) to an outer member 136, while the
non-bending portion 181 is at least partially disposed within the
sensor shaft 158.
[0331] FIG. 8 shows an exemplary embodiment of a flex sensing
assembly 156 equipped with a single flex sensor 170a, wherein the
sensor shaft 158 is coupled to the expansion and locking assembly
134, for example, to the outer member 136, and the flex sensor 170a
is coupled to a single strut 121a intersecting with the expansion
and locking assembly 134. In this configuration, since the sensor
shaft axis 22 remains oriented parallel to the expansion and
locking assembly 134 (which is usually parallel with the valve
longitudinal axis 20), the single flex sensor 170a can suffice for
derivation of the opening angle .beta. from a single angle
.alpha..sub.1 relative to the sensor shaft axis 22.
[0332] Reference is now made to FIGS. 9A-14E, showing different
embodiments of a flex sensing assembly 156. While all of the
embodiments illustrated throughout FIGS. 9A-14E show configurations
of flex sensing assemblies 156 equipped with two flex sensors,
coupled to two intersecting struts 121, this is for purposes of
illustrations only, and the same embodiments may in fact be
implemented with a single flex sensor, for example coupled to the
prosthetic valve 114 according to any one of the configurations
described and illustrated in conjunction with FIGS. 6A-8.
[0333] As described above, the flex sensor 170 may be operatively
coupled, for example via communication channel 160, to the control
unit 111.sup.a, and configured such that control unit 111.sup.a can
read the output of the flex sensor 170. In response to the flex
sensor 170 being flexed, the output of the flex sensor 170 changes.
According to some embodiments, the output of the at least one flex
sensor is an optic signal. According to some embodiments, the flex
sensing assembly 156 comprises an optic fiber assembly 257, wherein
the communication channel is provided in the form of an optic
conductor 260, and the flex sensor is provided in the form of an
optic flex sensor 270. Utilization of optic fiber sensors may be
advantageous due to their light weight, miniature dimensions, low
power consumption, high sensitivity, environmental ruggedness and
low cost.
[0334] FIG. 9A shows an exemplary embodiment of a flex sensing
assembly 156 equipped with two optic fiber assemblies 257, wherein
a first optic fiber assembly 257a comprises a first optic flex
sensor 270a coupled to a first strut 121a, and a second optic fiber
assembly 257b comprises a second optic flex sensor 270b coupled to
a second strut 121b. An example of a valve 114.sup.a is shown in
FIGS. 9A-9C with only two expansion and locking assemblies 134 for
clarity. However, any other number of expansion and locking
assemblies 134 (e.g., three) is contemplated. FIG. 9B shows a
zoomed-in view of region 9B in FIG. 9A.
[0335] According to some embodiments, the optic conductors 260 and
the respective optic flex sensor 270 are detachably optically
coupled to each other. Specifically, each optic fiber assembly 257
comprises an optic conductor 260 extending from the handle 110,
optionally through a lumen of the sensor shaft 158, up to an optic
conductor distal end 261, and an optic flex sensor 270 distal to
the optic conductor 260, coupled to a respective strut 121 (e.g.,
to a strut section 122). Each optic conductor 260 comprises an
optic conductor core 263, surrounded by an optic conductor cladding
262, and each optic flex sensor 270 comprises an optic sensor core
276 surrounded by an optic sensor cladding 274. Each of the optic
conductors 260 and/or optic flex sensor 270 can further include a
surrounding polymeric buffer coating (not shown) around the
claddings 262, 274, serving as an additional protective buffer from
the surrounding environment.
[0336] According to some embodiments, the outer diameter of the
optic conductor 260 is substantially equal to the outer diameter of
the optic flex sensor 270. According to some embodiments, the outer
diameter of the optic conductor core 263 is substantially equal to
the outer diameter of the optic sensor core 276.
[0337] The term `substantially equal`, when referring to a specific
measure as used herein, means no more and no less than 10% of the
measure. For example, a diameter of one component is substantially
equal to the diameter of a second component, if the diameter of the
first component is within the boundaries of 90%-110% of the second
diameter.
[0338] According to some embodiments, as further shown in FIGS.
9A-9B, each optic conductor 260 is detachably optically coupled to
the respective optic flex sensor 270. For example, each optic
conductor 260 may be detachably optically coupled to the respective
optic flex sensor 270.
[0339] According to some embodiments, the interface 164 of each
optic fiber assembly 257 is provided in the form of an optic
interface 264 between the optic conductor distal end 261 and the
optic sensor proximal end 272. The interface 264 is configured to
provide detachable optical coupling between the optic conductor 260
and optic flex sensor 270, such that signals may be communicated
there-between when optically coupled to each other, and wherein
both are optically decoupled when the optic conductor distal end
261 is detached from the optic sensor proximal end 272. Decoupling
of the optic conductor 260 from the second optic flex sensor 270
may be controlled by the handle 110, and may be facilitated by
applying a pull force exceeding a predefined threshold magnitude to
the optic conductor 260. According to some embodiments, decoupling
of the optic conductor 260 from the second optic flex sensor 270
may be executed simultaneously with the release of the actuators
151 from the expansion and locking assemblies 134, when implemented
for use with mechanically expandable valves 114.sup.a.
[0340] According to some embodiments, optical coupling between the
optic conductor 260 and the optic flex sensor 270 is achieved by
placement of the optic conductor distal end 261 in contact with the
optic sensor proximal end 272, and optical decoupling is achieved
by pulling the optic conductor distal end 261 away from the optic
sensor proximal end 272. In such embodiments, the interface 264
between the optic conductor 260 and the optic flex sensor 270 may
be defined as the contact area between the optic conductor distal
end 261 and the optic sensor proximal end 272.
[0341] According to some embodiments, the optical coupling of the
interface 264 is realized as a physical contact (PC) connection
between the optic conductor distal end 261 and the optic sensor
proximal end 272, wherein the optic conductor core 263 and the
optic sensor core 276 are aligned with each so as to optimize
performance and minimize optic light loss at the interface 264
there between.
[0342] According to some embodiments, the optical coupling 264 is
realized as a flat PC, when the optic conductor distal end 261 and
the optic sensor proximal end 272 comprise flat, and preferably
polished, end faces. According to some embodiments, the optical
coupling 264 is realized as an angled PC, when the optic conductor
distal end 261 and the optic sensor proximal end 272 comprise
complementary angled end faces, for example at an angle of about 8
degrees (embodiment not shown).
[0343] The term `about`, as used herein, means in a range of
.+-.10% from a referred value.
[0344] According to some embodiments, the interface 264 comprises
an optical connector, configured to releasably couple the optic
conductor distal end 261 and the optic sensor proximal end 272 and
allow signal communication there between. When communicating
signals between different optic fiber components, alignment of the
optic cores may be desirable, as even a slight misalignment may
lead to signal losses. According to some embodiments, an optical
connector 264 includes alignment features configured to align the
optic conductor distal end 261 and the optic sensor proximal end
272.
[0345] FIG. 9C shows the optic conductors 260 decoupled from the
optic flex sensors 270, being pulled along with the actuation
assemblies 150 in a proximally oriented direction 14, away from the
valve 114, while the optic flex sensors 270 remain coupled to the
valve 114, and more specifically, to the respective struts 121.
[0346] Optic signals are conventionally passed through optic cores.
To confine optic signals to the optic conductor core 263 and the
optic sensor core 276, their refractive index is typically greater
than that of the optic conductor cladding 262 and the optic sensor
cladding 274, respectively. According to some embodiments, optic
signals can pass through the optic conductor core 263 and the optic
sensor core 276 by means of total internal reflection. However, if
the angle of incidence of light striking the boundary between the
optic sensor core 276 and the optic sensor cladding 274 changes, a
proportional amount of the optic signal may pass outside of the
optic flex sensor 270 and not be reflected internally. As such, an
optic flex sensor 270 which flexes or bends, will exhibit some
degree of optic signal loss. Therefore, the extent of bending of an
optic flex sensor 270 can be detected by monitoring the optic
signals transmitted via the optic conductor 260.
[0347] According to some embodiments, the optic flex sensor 270
comprises a plurality of axially spaced Fiber Bragg Gratings (FBGs)
278, disposed along at least a portion of the optic sensor core
276. The reflected light from the optic sensor core 276 is a sum of
reflections from each of the FBGs along the optic sensor core 276.
Each reflection from each FBG may be modulated with a distinct
frequency (determined by the position of the FBG), enabling the
reflection spectrum to be separated using the data acquired from
the optic sensor core 276. The shift in each FBG is proportional to
the strain in the optic sensor core 276 at the location of the FBG,
such that the modulated optic signals are proportional to the
degree of bending applied at the axial location of the FBGs.
[0348] In use, a delivery assembly 100 may be utilized to deliver a
prosthetic valve 114 toward a desired implantation site in a
crimped state, having the optic flex sensors 270 coupled to
intersecting struts 121, while the optic conductors 260 are
optically coupled to the optic flex sensors 270.
[0349] Once the crimped valve 114 is positioned at the desired
implantation site, the handle 110 may be maneuvered to gradually
expand the valve 114 (for example, by pulling the actuators 151,
which are attached at this stage to the expansion and locking
assemblies 134, in the case of mechanically expandable valves
114.sup.a). During the expansion of the valve 114, the at least one
optic fiber assembly 257 provides real-time feedback in the form of
optic signals, correlated with flex of the optic flex sensor 270
coupled to a strut 121, from which the valve diameter may be
derived (in example, according to optic signals received from two
optic fiber assemblies 257, coupled to two intersecting struts
121). The data may be interpreted by the control unit 111.sup.a,
and may be visually displayed via a display 113a or LED lights 113b
positioned at the handle 110. The displayed interpreted data, which
can include real-time valve expansion diameter, may assist the
clinician in decision making regarding the next required steps of
the implantation procedure.
[0350] Once the valve 114 is sufficiently expanded, the handle 110
can be further maneuvered to release the actuation assemblies 150
from the valve 114 (if the valve is a mechanically expandable valve
114.sup.a), for example as elaborated above in conjunction with
FIGS. 4A-4C, and/or to decouple the optic conductors 260 from the
optic flex sensors 270, as elaborated above and shown in FIG.
9C.
[0351] FIGS. 9A-9C show an exemplary configuration in which the
interfaces 264 are located proximal to an intersection junction
124, wherein the intersection junction 124 is an outflow apex 125,
such that upon detachment from the optic conductors 260, the
non-bending portions 181 are shown to extend proximally from the
outflow apex 125. In alternative configurations, the intersection
junction 124 may be a non-apical junction, for example such as
proximal-most non-apical junction 124a distal to the outflow apices
125, such that upon detachment from the optic conductors 260, the
non-bending portion 181 will not extend proximally beyond the
outflow end 117.
[0352] While the interface 264 between the optically coupled optic
conductor 260 and optic flex sensor 270 is exemplified above as a
simple contact between their end faces, it will be clear that other
interfaces may be utilized for detachable optical coupling. For
example, the interface 264 may include a gap configured to transfer
light between the optic conductor 260 core 263 and optic sensor
core 276, with minimal interference. For example, the optic
conductor distal end 261 may be glued or fused to the optic sensor
proximal end 272 in a manner that application of a selected amount
of pull force, or alternatively, rotational force, can break the
adhesive bonds and allow the optic conductor 260 to be withdrawn,
and optically decoupled from the optic flex sensor 270.
[0353] While the optic fiber assembly 257 is described and
illustrated in conjunction with FIG. 9C above with a detachable
interface 264 between each optic conductor 260 and the respective
optic flex sensor 270, it will be clear that in alternative
embodiments, the optic fiber assembly 257 may be provided with a
non-detachable interface 264. For example, the optic conductors 260
may be pulled along with the optic flex sensor 270, away from the
valve 114, according to any of the embodiments that will be
described in conjunction with FIGS. 11A-14E below.
[0354] According to some embodiments, the output of the at least
one flex sensor is an electrical signal. The electrical signal can
be in the form of a current, a voltage, a resistance, or changes in
the same. For example, a flex sensor 170 can be configured such
that its resistance varies as a function of bending of the flex
sensor 170. In such embodiments, the communication channel 160 can
be provided in the form of an electric wire or cable, having its
distal end 161 electrically coupled at the interface 164 with the
flex sensor 170. For example, the interface 164 can include
electrical connection to end terminals (not shown) of the flex
sensor 170.
[0355] According to some embodiments, each communication channel
160 may include various electrically conductive materials, such as
copper, aluminum, silver, gold, and various alloys such as
tentalum/platinum, MP35N and the like. An insulator (not shown) can
surround each communication channel 160. The insulator can include
various electrically insulating materials, such as electrically
insulating polymers.
[0356] According to some embodiments, the at least one
communication channel 160 is further configured to deliver power to
the at least one sensor 170. According to some embodiments, the
communication channel 160 is connected to a proximal power source
(not shown), for example within the handle 110, configured to
provide power to operate the at least one flex sensor 170.
According to some embodiments, the communication channel 160 is
configured to deliver signals from, and/or to, the flex sensor
170.
[0357] According to some embodiments, an electrically conductive
communication channel 160 is releasably coupled to the flex sensor
170. In such embodiments, the communication channel 160 may be
coupled to the flex sensor 170 during prosthetic valve 114 delivery
to the implantation site, and during the implantation procedure,
and may be decoupled or released from the flex sensor 170 after the
implantation procedure is completed, allowing the communication
channel 160 to be retracted along with the remainder of the
delivery apparatus 102 from the patient's body. In such
embodiments, the prosthetic valve 114 may remain implanted in the
patient's body, having the at least one flex sensor 170 attached
thereto in a non-operative mode.
[0358] Reference is now made to FIGS. 10A-10C, illustrating a
non-binding configuration of a detachable coupling mechanism
between a communication channel 160 and a flex sensor 170.
According to some embodiments, as shown in FIG. 10A, the flex
sensor assembly 156 further comprises at least one sensor housing
374 attached to a strut 121, and at least one detachable shaft 358
extending distally from the handle 110, having least a portion of
the a corresponding communication channel 160 extending through a
lumen thereof, and axially movable relative thereto. The valve 114
is shown in FIGS. 10A-10C with only two actuator assemblies 134 for
clarity. However, any other number of actuator assemblies 134
(e.g., three) is contemplated.
[0359] According to some embodiments, the at least one flex sensor
170 is at least partially retained within a sensor housing 374, and
is locally affixed to the sensor housing 374, for example by
gluing, welding, and the like. The sensor housing 374 may be
provided with a lumen, a bore, or any other channel for
accommodating the flex sensor 170. The sensor housing 374 may be
affixed to the respective strut 121, for example by gluing,
welding, or an affixing coupling member 188. Additionally or
alternatively, the sensor housing 374 may be coupled to the strut
121 via at least one non-affixing coupling member 188.
[0360] The term "locally affixed", as used herein with reference to
the flex sensor 170, means that the flex sensor is rigidly affixed
to the respective sensor housing 374 at a local point or region of
the flex sensor 170 (e.g., a proximal region thereof), while at
least one other portion thereof (e.g., a distal portion) is not
affixed to the sensor housing 170, so as to enable axial
displacement of at least a portion of the flex sensor 170 relative
to the respective strut 121, during valve expansion or
compression.
[0361] According to some embodiments, the at least one
communication channel 160 extends through a lumen of the detachable
shaft 358, wherein the detachable shaft 358 is detachably coupled
to the sensor housing 374. The communication channel 160 may
further extend into the sensor housing 374, and is detachably
coupled to the flex sensor 170. The detachable shaft 358 is
configured to isolate the communication channel 160 extending
there-through, and the interface 164 with the flex sensor 170, from
the ambient flow (e.g. blood flow), when the detachable shaft 358
is coupled to the sensor housing 374.
[0362] FIGS. 10A-10C illustrate an embodiment of sensor housings
374 provided in the form of sleeves or tubes, accommodating the
entire length of respective flex sensors 170 within lumens or bores
thereof. In alternative embodiments, each sensor housing 374 may be
provided as a short nut-like member (not shown), having the
respective flex sensor 170 extending through a central bore
thereof, while at least a portion of the flex sensor 170 extends
further distally away from the sensor housing 374, and may be
coupled to the respective strut 121 via at least one non-affixing
coupling member 188.
[0363] According to some embodiments, the communication channel
distal end 161 is detachably coupled to the flex sensor proximal
end 172 at interface 364. Similarly, the detachable shaft distal
end 359 (see FIG. 10C) is detachably coupled to the sensor housing
proximal end 375. According to some embodiments, the sensor housing
proximal end 375 comprises a threaded bore (see FIG. 10C), and the
detachable shaft distal end 359 comprises an external threading,
configured to threadedly engage with the sensor housing threaded
bore 375.
[0364] In the state shown in FIG. 10A, the first 161a and second
161b communication channel distal ends are coupled to the first
172a and second 172b flex sensor proximal ends, respectively, and
the first 359a and second 359b detachable shaft distal threaded
ends are coupled to (e.g., threaded with) the first 375a and second
375b sensor housing proximal threaded ends, respectively. In this
state, power may be supplied to the flex sensor 170a and 170b via
the communication channels 160a and 160b, respectively, and signals
may be transmitted from and to the flex sensors 170a and 170b via
the communication channels 160a and 160b, respectively.
[0365] FIG. 10B shows a state during disengagement of the
communication channels 160a and 160b from the flex sensors 170a and
170b, respectively. According to some embodiments, each
communication channel 160 may be coupled to the respective sensor
170 such that application of a pull force in the proximal direction
14, beyond a predetermined threshold magnitude, may disengage the
communication channel 160 from the flex sensor 170. According to
some embodiments, the force required to disengage the communication
channel 160 from the flex sensor 170 may be applied manually.
According to some embodiments, the force required to disengage the
communication channel 160 from the flex sensor 170 may be applied
by a mechanical or electrical actuation mechanism at the handle
110.
[0366] As shown in FIG. 10B, while the communication channel 160 is
decoupled from the flex sensor 170, the detachable shaft 358
remains coupled to the sensor housing 374, thereby isolating the
communication channel 160 from the surrounding environment of the
blood flow. This allows the communication channel 160 to be
detached and pulled from the flex sensor 170 while avoiding the
risk of exposing the surrounding blood flow or other tissues to
electrical current thereof.
[0367] Once the communication channel 160 is detached from the flex
sensor 170 and pulled away therefrom, the detachable shaft 358 may
be rotated, for example in a direction 16 around its axis of
symmetry, so as to detach from the sensor housing 374. According to
some embodiments, the communication channel 160 is pulled along a
sufficient distance prior to disengaging the detachable shaft 358
from the sensor housing 374, such that once the detachable shaft
358 is detached, the communication channel 160 cannot be exposed to
the blood flow flowing through the lumen of the detachable shaft
358.
[0368] According to some embodiments, the detachable shaft 358
extends through a lumen of the sensor shaft 158. Alternatively, the
detachable shafts 358 may extend through the lumen of the delivery
shaft 106, without an additional dedicated sensor shaft 158.
[0369] FIG. 10C shows a more advanced state of disengagement of the
communication channels 160 from the flex sensors 170, compared to
the state shown in FIG. 10B. The state shown in FIG. 10C is
achieved by further pulling the detachable shaft 358 in a proximal
direction 14, away from the sensor housing 374, after being
disengaged therefrom. This mechanism allows the communication
channel 160, along with the detachable shaft 358, to be disengaged
from the flex sensor 170 and sensor housing 374, and retracted from
the patient's body at the end of the implantation procedure,
without risking exposure of the native tissues or blood flow to
electrical current flowing through the communication channel 160
during such disengagement.
[0370] While the detachable coupling mechanism described
hereinabove and illustrated in FIGS. 10A-C, is described as
advantageous when utilized with electrically conductive
communication channels 160 and flex sensors 170, it will be clear
that the same mechanism can be similarly utilized for optic
components, such as optic conductors 260 and optic flex sensors
270, respectively.
[0371] As mentioned above, the flex sensing assembly 156 may be
fully detachable from the prosthetic valve 114, to facilitate
delivery apparatus 102 retrieval once the valve is fully deployed
and mounted in position. FIGS. 11A-B show an exemplary embodiment
of a flex sensing assembly 156 equipped with at least one flex
sensor 170 coupled to a strut 121. It will be clear that while a
configuration of two flex sensors 170 coupled to two intersecting
struts 121 is shown, the embodiments are similarly applicable for a
single flex sensor 176 (according to the configurations shown in
FIGS. 6A-8, for example), or more than two flex sensors. In order
to avoid undue clutter from having too many reference numbers and
lead lines on a particular drawing, numerals are assigned only to
some components in FIGS. 11A-B, for example--only to the first flex
sensor 170a, first communication channel 160a, and so on.
[0372] In the illustrated embodiment, each flex sensor 170 is
coupled to a respective strut 121 via a plurality of coupling
members 188 which are non-affixing coupling members, for example in
the form of suture loops or bands 188. The sutures or bands 188 may
be tightly wrapped around the flex sensor 170 and the respective
strut 121, configured to retain the flex sensor 170 in place over
the strut 121 by facilitation frictional forces between the
coupling member 188 and the flex sensor 170 and/or the strut 121.
The coupling members 188 are configured to allow at least a portion
of the flex sensor 170 to slide forward or backward relative to the
strut 121 it is coupled to. This may advantageously prevent the
flex sensor 170 from over-stretching during valve expansion, for
example.
[0373] In most cases, it is sufficient to couple the flex sensor
170 to a strut portion 122, between the intersection junction 124
and an adjacent junction, for example--a distal junction along the
same strut 121. According to some embodiments, as shown for example
in FIG. 5C, the flex sensor 170 comprises a sensor distal portion
182, which is configured to extend beyond the most distal coupling
member 188 during the entire valve range of diameters, between the
crimped state and the fully expanded state. In such embodiments,
the minimal length of sensor distal portion 182 may be defined as
the shortest distal portion of the flex sensor 170, extending
beyond the most distal coupling member 188, at the valve fully
expanded state. In some variants of the embodiments, the minimal
length of the sensor distal portion 182 is chosen so as to prevent
the flex sensor 170 from slipping out of the most distal coupling
member 188 during transition from a crimped state to a fully
expanded state of the valve 114.
[0374] According to some embodiments, the sensor distal portion 182
may be flexibly curved sideways, away from the axial direction of
the strut 121 it is attached to, to provide additional retaining
force, preventing spontaneous displacement of the flex sensor 170
relative to the strut 121 it is coupled to. The flexibility of the
sensor distal portion 182 allows it to easily slip through the
coupling members 188 when a force is applied thereto, for example,
during valve expansion.
[0375] According to some embodiments, as shown in FIGS. 11A-B, the
flex sensing assembly 156 further comprises a flexible distal
extension 184, attached to and extending distally from, the flex
sensor distal end 173. The flexible distal extension 184 may be
provided in the form of a wire, a cable and the like. The minimal
length of the flexible distal extension 184 may be chosen to have
at least a portion thereof extending beyond the most distal
coupling member 188 during transition from a crimped state to a
fully expanded state of the valve 114.
[0376] According to some embodiments, as shown in FIG. 11A, the
flexible distal extension 184 may be resiliently curved sideways,
away from the axial direction of the strut 121 the respective flex
sensor 170 it is attached to, to provide additional retaining force
that prevents spontaneous displacement of the flex sensor 170
relative to the strut 121 it is coupled to. The resiliency and
flexibility of the distal extension 184 allows it to easily slip
through the coupling members 188 when an axial force is applied
thereto, for example, during valve expansion.
[0377] Once the desired diameter of the prosthetic valve 114 is
reached, the flex sensing assembly 156 may be pulled in a
proximally oriented direction, wherein the pull force applied
thereto is sufficient to overcome friction forces or any other
forces applied by the coupling members 188 to couple the flex
sensors 170 to the struts 121. According to some embodiments, the
pull force for decoupling the flex sensing assembly 156 from the
valve 112 may be applied manually. According to some embodiments,
the pull force for decoupling the flex sensing assembly 156 from
the valve 114 may be applied by a mechanical or electrical
actuation mechanism at the handle 110.
[0378] As shown in FIG. 11B, during retraction of the flex sensing
assembly 156, the flex sensors 170, along with the distal
extensions 184, are pulled through the respective coupling members
188, for example, through the suture loops or bands 188. If the
flexible distal extensions 184 are naturally curved, as shown in
FIG. 11A, such curves may be easily straightened as the distal
extensions 184 are pulled through the coupling members 188, as
shown in FIG. 11B. While FIG. 11B illustrates a state in which the
actuation assemblies 150 are detached and spaced away from the
valve 114.sup.a, while at least a portion of the flex sensing
assembly 156 (e.g., flexible distal extensions 184), is in the
process of detachment and may still partially extend through at
least some of the coupling members 188, this is for purpose of
illustration only. Decoupling of the flex sensing assembly 156 may
be performed prior, during or after detachment of the actuation
assemblies 150 (in the case of mechanically expandable valve
114.sup.a, for example). According to some embodiments, the handle
110.sup.a comprises a mechanism (not shown) configured to
facilitate simultaneous detachment and retraction of both the
actuation assemblies 150 and the flex sensing assembly 156,
preferably via a single knob operable by an operator or user of the
handle 110.sup.a.
[0379] According to some embodiments, the flex sensor 170 comprises
a flexible sensor substrate 176, and a variable resistance element
178. The flexible sensor substrate may extend along the entire
length between the flex sensor proximal end 172 and the flex sensor
distal end 173, while the variable resistance element 178 may
extend along a portion of the flex sensor 170, between the flex
sensor proximal end 172 and a position that may be proximal to the
flex sensor distal end 173. According to some embodiments, the
sensor distal portion 182 comprises a portion of the flexible
sensor substrate 176, but is devoid of a variable resistance
element 178.
[0380] According to some embodiments, the variable resistance
element 178 is attached to or embedded in the flexible sensor
substrate 176. For example, the flexible sensor substrate 176 may
include a silicon or rubber casing, or and the variable resistance
element 178 may be molded in the substrate casing 176 to protect it
from the corrosive environment inside the vascular system, by
sealing it from body fluids. According to some embodiments, the
variable resistance element 178 includes terminals or other
electrical connectors, configured to electrically connect, at
interface 164, with the corresponding communication channel
160.
[0381] According to some embodiments, the processing unit at the
handle 110 is configured to apply voltage, delivered via the
communication channels 160 and through the terminals at interface
164, to the variable resistance elements 178 of the flex sensors
170, and to measure electrical resistance. A relationship between
the degree of flex angle (e.g., .alpha..sub.1, .alpha..sub.2,
.gamma.) and the resistance (or alternatively, the optical signals)
can be developed and used in software included in the control unit
111.sup.a.
[0382] According to some embodiments, the flexible sensor substrate
176 is provided in the form of a polymer sheet or elongated strip,
and may include polyamide or any other type of an elastomer.
[0383] According to some embodiments, the variable resistance
element 178 is provided in the form of a strain gauge or other type
of a flexible potentiometer, configured to vary its electrical
resistivity in response to the extent of bending applied thereto.
Changes in resistivity produce a corresponding changes in voltage
that can be processed by the control unit 111.sup.a, to determine
change in valve diameter.
[0384] FIGS. 12A-B show an exemplary embodiment of a flex sensor
170 comprising a variable resistance element 178 in the form of a
strain gauge, disposed along a portion of the sensor substrate 176.
It will be clear that while a configuration of two flex sensors 170
coupled to two intersecting struts 121 is shown, the embodiments
are similarly applicable for a single flex sensor 170 (according to
the configurations shown in FIGS. 6A-8, for example), or more than
two flex sensors. In order to avoid undue clutter from having too
many reference numbers and lead lines on a particular drawing,
numerals are assigned only to some components in FIGS. 12A-B, for
example--only to the first flex sensor 170a, first communication
channel 160a, and so on.
[0385] According to some embodiments, the strain gauge 178, as
shown in FIGS. 12A-B, is provided with a meandering structure,
which may advantageously increase resistance variation under flex
thereof.
[0386] According to some embodiments, the coupling member 188 may
include a tubular member, as shown in FIG. 11A, through which the
flex sensor 170 may slide backward and forward. While shown in
combination with a flex sensor 170 having a strain gauge 178, it
will be clear that this is for illustrative purpose only, and that
a tubular coupling member 188 may be employed in combination with
any other embodiment of flex sensors disclosed herein.
[0387] As shown in FIG. 12B, during retraction of the flex sensing
assembly 156, the flex sensors 170 are pulled through the
respective coupling members 188, for example, through the tubular
members 188. If the sensor distal portions 182 are naturally
curved, such curves may be easily straightened as the sensor distal
portions 182 are pulled through tubular coupling members 188, as
shown in FIG. 12B. While FIG. 12B illustrates a state in which the
actuation assemblies 150 are detached and spaced away from the
valve 114.sup.a, while at least a portion of the flex sensing
assembly 156 (e.g., sensor distal portions 182), is in the process
of decoupling and may still partially extend through at least a
portion of tubular members 188, this is for purpose of illustration
only, and decoupling of the flex sensing assembly 156 may be
performed prior, during or after detachment of the actuation
assemblies 150 (in the case of mechanically expandable valve
114.sup.a, for example).
[0388] According to some embodiments, the variable resistance
element 178 is provided in the form of a conductive material layer,
disposed over at least a portion of the flexible sensor substrate
176 and configured to change its resistance with the degree of flex
applied thereto. The conductive material layer can include graphite
in combination with a binder. According to some embodiments, the
variable resistance element 178 is provided in the form of
conductive ink. The material of the variable resistance element 178
may be sprayed, rolled, silk-screened, brushed or otherwise printed
onto the flexible sensor substrate 176.
[0389] FIGS. 13A-B show an exemplary embodiment of a flex sensor
170 comprising a variable resistance element 178 in the form of a
conductive material layer, disposed over a portion of the sensor
substrate 176. It will be clear that while a configuration of two
flex sensors 170 coupled to two intersecting struts 121 is shown,
the embodiments are similarly applicable for a single flex sensor
170 (according to the configurations shown in FIGS. 6A-8, for
example), or more than two flex sensors. In order to avoid undue
clutter from having too many reference numbers and lead lines on a
particular drawing, numerals are assigned only to some components
in FIGS. 13A-B, for example--only to the second flex sensor 170b,
second communication channel 160b, and so on.
[0390] The conductive material layers 178 may be electrically
coupled to the respective communication channels 160 at the
interfaces 164, as shown in FIG. 13A.
[0391] According to some embodiments, the coupling members 188 are
provided as geometrical features integrally formed with components
of the prosthetic valve 114. According to some embodiments, as
shown in FIG. 11A, the struts 121 configured to interact with the
flex sensing assembly 156 are provided with at least one strut
aperture 123, and preferably at least two strut apertures 123
formed along each strut 121 to which a flex sensor 170 may be
coupled. In the illustrated embodiment, each flex sensor 170 may
extend into one strut aperture 123, for example, at a proximal
position in the vicinity of the intersection junction 124, and out
of a subsequent junction provided along the same strut 121.
[0392] In some applications, the strut apertures 123 are
through-holes, enabling the flex sensor 170 to extend through each
apertures from one side of the strut 121 to the other side, such
that at least a portion of the flex sensor 170 is disposed along an
inner surface of the strut 121 (i.e., a surface facing radially
inward), and at least a portion of the flex sensor 170 is disposed
along an outer surface of the strut 121 (i.e., a surface facing
radially outward).
[0393] In some applications, the strut 121 is provided with an
internal channel (not numbered) extending between two strut
aperture 123. In such applications, the flex sensor 170 may be
inserted into the strut channel through one strut aperture 123, and
exit from the channel through another, such that at least a portion
of the flex sensor 170 is disposed within the internal strut
channel.
[0394] While shown in combination with a flex sensor 170 having a
conductive material layer 178, it will be clear that this is for
illustrative purpose only, and that a struts 121 with strut
apertures 123 may be employed in combination with any other
embodiment of flex sensors disclosed herein.
[0395] As shown in FIG. 13B, during retraction of the flex sensing
assembly 156, the flex sensors 170 are pulled through the
respective strut apertures 123. If the sensor distal portions 182
are naturally curved, such curves may be easily straightened as the
sensor distal portions 182 are pulled through strut apertures 123.
While FIG. 13B illustrates a state in which the actuation
assemblies 150 are detached and spaced away from the valve 114,
while at least a portion of the flex sensing assembly 156 (e.g.,
sensor distal portions 182), is in the process of decoupling and
may still partially extend through at least some of the strut
apertures 123, this is for purpose of illustration only, and
decoupling of the flex sensing assembly 156 may be performed prior,
during or after detachment of the actuation assemblies 150 (in the
case of mechanically expandable valve 114.sup.a, for example).
[0396] According to some embodiments, the flex sensing assembly 156
further comprises a flexible elongated member 186, extending
distally from the handle 110 to the flexible distal extension 184,
configured to couple at least two flexible distal extension 184 to
each other, and to allow separation thereof upon being pulled in a
proximally oriented direction 14.
[0397] FIGS. 14A-E shows different stages of utilizing a flex
sensing assembly 156 equipped with a flexible elongated member 186,
according to some embodiments. The flex sensing assembly 156
comprises two flexible distal extensions 184, which are similar in
structure and function to the flexible distal extensions 184
described in conjunction with FIGS. 11A-B, except that each
flexible distal extension 184 may further include a distal loop
185. The first distal loop 185a of the first flexible distal
extensions 184a may be engaged with the second distal loop 185b of
the second flexible distal extensions 184b, respectively, by the
flexible elongated member 186 extending through both.
[0398] The flexible elongated member 186 may be provided as a
flexible string, suture, wire, cable, and the like, and may extend
through the delivery shaft 106, through the sensor shaft 158,
and/or through another dedicated shaft (not shown).
[0399] In a first stage shown in FIG. 14A, the flexible elongated
member 186 extends through the open space contoured by each of the
first distal loop 185a and second distal loop 185b, which may be
aligned with each other. The flexible elongated member 186 may
extend distally from the handle 110 to the distal loops 185, and
bend over through the loops 185, having a flexible member end
portion 187 extending proximally therefrom.
[0400] In order to initiate retraction of the flex sensing assembly
156, the flexible elongated member 186 may be pulled in a
proximally oriented direction, as shown in FIG. 14B, such that the
bent over flexible member end portion 187 becomes shorter, until it
is fully withdrawn from the loops 185. The handle 110 may include a
controllable mechanism for pulling the flexible elongated member
186.
[0401] As shown in FIG. 14C, once the flexible elongated member 186
is completely withdrawn, the first distal loop 185a and the second
distal loop 185b are no longer coupled to each other, allowing the
flex sensors 170 to be retracted, along with the distal extensions
184. A flex sensing assembly 156 equipped with a flexible elongated
member 186 may be utilized in combination with coupling members 188
according to any of the previous embodiments. FIG. 14E shows both
the actuation arm assemblies 150 and the flex sensing assembly 156,
detached and spaced away from the prosthetic valve 114.
[0402] According to some embodiments, the distal loops 185 are
open-ended loops, formed by pre-shaping the end portions of the
distal extensions 184 to resiliently form a loop-shaped
configuration, while the end of the distal extensions 184 remain
free ended (i.e., unconnected to other regions thereof). Open-ended
distal loops 185 (as shown in FIGS. 14A-E) may be easily
straightened, as the distal extensions 184 are pulled through
coupling members 188, such as suture loops or bands 188. According
to alternative embodiments, the distal loops 185 are close-ended
loops (not shown), which are flexible enough to be able to contract
while being pulled through coupling members 188, such as suture
loops or bands 188.
[0403] An advantage conferred by the delivery assemblies and the
methods disclosed herein, is that they enable continuous real-time
diameter monitoring, thereby providing valuable feedback to the
clinician with respect to the valve expansion within the native
anatomy. This valuable information may assist in preventing, or at
least reducing, potential trauma to a tissue (e.g., the annulus).
The clinician can continuously readjust the diameter of the
prosthetic valve 114 as necessary, until the prosthetic valve 114
is expanded to a diameter that best fits the native annulus. For
example, a diameter which is sufficient to anchor the prosthetic
valve 114 in place against the surrounding tissue, with little or
no paravalvular leakage, and without over-expanding the prosthetic
valve 114 so as to avoid, or reduce the risk of, native annulus
rupture.
[0404] A prosthetic valve 114 of the current disclosure may include
any prosthetic valve configured to be mounted within the native
aortic valve, the native mitral valve, the native pulmonary valve,
and the native tricuspid valve. While a delivery assembly 100
described in the current disclosure, includes a delivery apparatus
102 equipped with a flex sensing mechanism 156 and a prosthetic
valve 114, it should be understood that the delivery apparatus 102
equipped with a flex sensing mechanism 156 according to any
embodiment of the current disclosure can be used for implantation
of other prosthetic devices aside from prosthetic valves, such as
stents or grafts.
[0405] While the embodiments are described and illustrated
throughout FIGS. 1-14E for use with a mechanically expandable valve
114.sup.a, it will be clear that flex sensing assemblies 156
according to any of the embodiments disclosed herein may be
similarly used in combination with other valve types, such as
balloon expandable valves or self-expandable valves. However,
conventional balloon-expandable valves and self-expandable valves
are typically inflated or expanded during a short time period
(e.g., in a burst), in a manner which provides limited control of
valve expansion. In contrast, utilization of flex sensing
assemblies 156 in combination with mechanically expendable valves
114.sup.a is advantageous since the mechanical expansion mechanism
(for example--as described in conjunction with FIGS. 4A-C) provides
a higher degree of control over the rate and extent of valve
expansion, enabling the clinician to adjust expansion diameter,
responsive to real-time feedback provided by the flex sensing
assembly 156.
[0406] Recently, balloon expandable valves that can be expanded
within a range of functional sizes have been developed, such as
disclosed in U.S. Patent Application Publication No. 2018/0028310,
which is incorporated herein by reference. For the implantation of
such prosthetic valves, the physician conventionally selects an
appropriate volume of the inflation fluid corresponding to a
selected prosthetic valve diameter from a range of fill volumes.
Using a conventional inflation syringe, it can be difficult for the
physician to draw the precise amount of inflation fluid into the
syringe that is required to expand a prosthetic valve to a desired
size if the required volume does not correspond with one of the
volume indicators provided on the syringe. Moreover, the amount of
inflation fluid is not necessarily correlated with a specific
expansion diameter, as the balloon may extend longitudinally as
well as expand diametrically, making it hard to predict radial
expansion based solely on a known amount of fluid inflation. Thus,
the valve expansion mechanism is herein modified to allow more
controlled inflation methods.
[0407] Additionally, in order to take advantage of any of the flex
sensing assemblies described hereinabove in conjunction with FIGS.
5A-14E, for use with balloon expandable valves, the expansion
mechanism is herein modified to allow the balloon to be inflated
and/or deflated in a gradual and controllable manner, thereby
allowing the clinician to adjust balloon inflation according to the
measured expansion diameter.
[0408] FIG. 15 shows an example of a frame 120.sup.b of a balloon
expandable valve 114.sup.b. The frame 120.sup.b comprises a
plurality of struts 121.sup.b that can include angled strut
portions 122.sup.b(1) and vertical strut portions 122.sup.b(2). In
such embodiments, the struts 121.sup.b may be pivotable or bendable
relative to each other, so as to permit frame expansion or
compression. For example, the frame 120.sup.b can be formed from a
single piece of material, such as a metal tube, via various
processes such as, but not limited to, laser cutting,
electroforming, and/or physical vapor deposition, while retaining
the ability to collapse/expand radially in the absence of hinges
and like.
[0409] FIG. 16 shows an example of a delivery assembly 100.sup.b
comprising a delivery apparatus 102.sup.b for delivery and
implantation of balloon expandable valve 114.sup.b. According to
some embodiments, the delivery apparatus 102.sup.b includes a
balloon catheter 107 having an inflatable balloon 105 (shown, for
example, in an inflated state in FIG. 17B) mounted on its distal
end. The balloon expandable prosthetic valve 114.sup.b can be
carried in a crimped state over the inflatable balloon 105, as
shown in FIG. 17A. The delivery apparatus 102.sup.b can include a
delivery shaft 106.sup.b and/or an outer shaft 104.sup.b that in
some cases, can concentrically extend over the balloon catheter
107. The delivery apparatus 102.sup.b can additionally include a
nosecone 109 attached to a distal end of a nosecone shaft 108, and
a distal end of the inflatable balloon 105 can extend over the
nosecone 109.
[0410] The proximal ends of the balloon catheter 107, and when
present--the delivery shaft 106.sup.b and/or the outer shaft
104.sup.b, can be coupled to the handle 110.sup.b. During delivery
of the prosthetic valve 114.sup.b, the handle 110.sup.b can be
maneuvered by an operator (e.g., a clinician or a surgeon) to
axially advance or retract components of the delivery apparatus
102.sup.b, such as the nosecone shaft 108, the balloon catheter
107, the delivery shaft 106.sup.b and/or the outer shaft 104.sup.b,
through the patient's vasculature, as well as to inflate the
balloon 105 mounted on the balloon catheter 107, so as to expand
the prosthetic valve 114.sup.b, and to deflate the balloon and
retract the delivery apparatus 102.sup.b once the prosthetic valve
114.sup.b is mounted in the implantation site.
[0411] According to some embodiments, the delivery assembly
100.sup.b further comprises an inflation fluid system 200. The
inflation fluid system 200 can comprise: a reservoir 210 that can
contain a predetermined volume of inflation fluid 212; a fluid flow
channel 220 defined between a proximal end 222 and a distal end
224; and a pump 230. Distal end 224 can be in fluid communication
with an inlet port 225 of the balloon 105. The inlet port 225 of
the balloon 105 can be located at the proximal end thereof. The
inflation fluid 212 can be liquid, and can further comprise
saline.
[0412] The term "fluid communication", as used herein, means that
fluid can flow between components in fluid communication with each
other. The fluid communication can be accomplished via a direct
connection between openings of the respective components or via
additional components connected therebetween.
[0413] According to some embodiments, the pump 230 can be in fluid
communication with both the reservoir 210 and the proximal end 222
of the fluid flow channel 220. A control input of the pump 230 can
be in communication with a control unit 111.sup.b. Control unit
111.sup.b can be positioned within the inflation fluid system 200,
within the handle 110.sup.b or at any other suitable location.
According to some embodiments, control unit 111.sup.b can comprises
a plurality of components, with some of the components being
positioned within the inflation fluid system 200, some of the
components being positioned within the handle 110.sup.b and/or some
of the components being positioned in other suitable locations.
[0414] Control unit 111.sup.b can include a central processing unit
(CPU), a microprocessor, a microcomputer, a programmable logic
controller, an application-specific integrated circuit (ASIC)
and/or a field-programmable gate array (FPGA), without limitation.
According to some embodiments, the control unit 111.sup.b can
further comprise a memory. According to some embodiments, selected
data, such as raw signal data or calculated data, may be stored in
the memory. According to some embodiments, the control unit
111.sup.b can be configured to log data during the implantation
procedure in the memory. According to some embodiments, the control
unit 111.sup.b can be configured to transmit to a remote device,
logged data from the memory, and/or real-time data.
[0415] According to some embodiments, a flow meter 236 and/or a
pressure sensor 238 is provided. The flow meter 236 can be coupled
between the pump 230 and the reservoir 210, as shown. The pressure
sensor 238 can be coupled between the pump 230 and the balloon 105,
as shown. Although the pressure sensor 238 is illustrated as being
near pump 230, this is not meant to be limiting in any way, and the
pressure sensor 238 can be positioned anywhere along the fluid
path, including within the balloon 105. Each of the flow meter 236
and the pressure sensor 238 can be in communication with control
unit 111.sup.b. The control unit 111.sup.b can control the pump 230
to adjust the flow of the inflation fluid 212. Adjustment of the
flow of the inflation fluid 212 can include adjustment of the flow
rate and/or the amount of inflation fluid 212 that flows into the
balloon 105.
[0416] The flow adjustment of control unit 111.sup.b can be
responsive to a user input, such as the amount of inflation fluid
212 to be injected into the balloon 105. Additionally, or
alternately, the flow adjustment of control unit 111.sup.b can be
responsive to the flow meter 236 and/or the pressure sensor 238,
such that the flow of the inflation fluid 212 remains within
predetermined parameters. Additionally, or alternately, the flow
adjustment of control unit 111.sup.b can be responsive to
additional sensors coupled to the valve and/or balloon, as will be
described below. According to some embodiments, the control unit
111.sup.b can further control the pump 230 to reverse the flow of
the inflation fluid 212, thereby removing some, or all, of the
inflation fluid 212 from the balloon 105.
[0417] According to some embodiments, the pressure sensor 238
measures the pressure of the inflation fluid 212 flowing into the
balloon 105. The pressure sensor 238 can comprise dedicated
circuitry for operation and/or for pressure measurement.
Alternatively, or additionally, the pressure sensor 238 can be
operated in cooperation with the control unit 111.sup.b. The
measurement can be performed while the inflation fluid 212 is
flowing into the balloon 105 and/or when the control unit 111.sup.b
controls the pump 230 to cease the flow of the inflation fluid 212.
Control unit 111.sup.b can compare the measured pressure of the
inflation fluid 212 to a predetermined maximum pressure threshold
value.
[0418] According to some embodiments, the control unit 111.sup.b
can be configured to control the pump 230 to adjust the flow of the
inflation fluid 212 responsive to an outcome of the comparison.
Responsive to the measured pressure being greater than the
predetermined maximum pressure threshold value, the control unit
111.sup.b can control the pump 230 to cease the flow of the
inflation fluid 212 and/or control the pump 230 to reverse the flow
of the inflation fluid 212 thereby reducing the pressure. The
measured pressure can be output at a user display and the control
unit 111.sup.b can be configured to adjust the flow of the
inflation fluid responsive to a respective user input.
[0419] According to some embodiments, the control unit 111.sup.b
can compare the measured pressure to a predetermined minimum
pressure threshold value. According to some embodiments, the
predetermined minimum pressure threshold value can be substantially
the same of the predetermined maximum pressure threshold value. The
control unit 111.sup.b can be configured to control the pump 230 to
adjust the flow of the inflation fluid 212 responsive to an outcome
of the comparison. Responsive to the measured pressure being less
than the predetermined minimum pressure threshold value, the
control unit 111.sup.b can control the pump 230 to increase the
flow rate of the inflation fluid 212, and/or the amount of
inflation fluid 212 flowing into the balloon 105, thereby
increasing the pressure.
[0420] Expansion of the valve 114.sup.b against the surrounding
tissue may pose a variety of risks associated with a mismatch
between the valve's expansion diameter and the surrounding tissue.
One complication is related to valve over-expansion, which may
exert excessive radial forces on the surrounding anatomy, resulting
in potential damage to the tissue or even annular rupture. On the
other hand, valve under-expansion might increase the risk of aortic
valve or mitral valve regurgitation. Inappropriate expansion may
also result in unfavorable hemodynamic performance across the valve
114.sup.b, such as increased pressure gradients or flow
disturbances resulting from diameter mismatch, which may be
associated with increased risk of thrombus formations.
[0421] Advantageously, the control unit 111.sup.b, in cooperation
with the pressure sensor 238, can monitor the pressure of the
inflation fluid 212, which exhibits a direct relationship to the
radial forces on the surrounding tissue, and control the pump 230
to maintain the pressure within a desired predetermined range. This
can avoid the deleterious effects of annular rupture, inferior
hemodynamic performance and valve regurgitation, arising due to
either over-expansion or under-expansion, respectively, of the
valve 114.sup.b.
[0422] FIG. 17A shows the valve 114.sup.b mounted on the balloon
catheter 107 in a crimped configuration for delivery into the body.
The balloon catheter 107 comprises the inflatable balloon 105 for
expanding the valve within the patient's body, the crimped valve
114.sup.b being positioned over the deflated balloon 105 during
delivery. According to some embodiments, the delivery apparatus
102.sup.b further comprises a pusher 103 that can be used to
facilitate passage of the valve 114.sup.b through a shaft (e.g., an
outer shaft 104.sup.b) of the delivery assembly 100.sup.b.
[0423] FIG. 17B shows the balloon 105 in an inflated state, causing
the prosthetic valve 114.sup.b to radially expand into contact with
the surrounding anatomy (e.g., into contact with the aortic
annulus, in the case of aortic valve replacement procedures). The
balloon catheter 107 is shown protruding through the pusher 103 and
the valve 114.sup.b. In some occasions, the frame 120.sup.b may be
slightly over-expanded to account for any spring-back in the
material. The pusher 103 can be utilized to push the frame 120 over
the balloon 105 in configurations in which the crimped balloon is
positioned proximal to the balloon during delivery to the
implantation site, for example to reduce overall crimp profile
during such delivery through the patient's vasculature.
[0424] Once the valve 114.sup.b is fully expanded, the balloon 105
is deflated and remove along with the remainder of the delivery
apparatus 102.sup.b. Because the frame 120.sup.b is
plastically-deformable, it substantially retains its expanded
state. According to some embodiments, the balloon 105 can be
deflated by control unit 111.sup.b controlling the pump 230 to
reverse the flow of the inflation fluid 212 thereby emptying the
balloon 105 of the inflation fluid 212. Furthermore, the control
unit 111.sup.b can control the pump 230 to remove only a portion of
the inflation fluid 212 from within the balloon 105, as will be
described below.
[0425] According to some embodiments, at least one diameter sensor
is provided. The output of the at least one diameter sensor is
responsive to the radial diameter of the inflatable balloon 105
and/or the frame 120.sup.b. The control unit 111.sup.b is in
communication with the at least one diameter sensor and can
determine an indication of the radial diameter of the inflatable
balloon 105 and/or the frame 120.sup.b, as described below. As
described below, the indication of the radial diameter can comprise
the difference between an initial radial diameter and a present
radial diameter. The term "initial radial diameter", as used
herein, means the radial diameter of the inflatable balloon 105
and/or frame 120.sup.b at a predetermined time. The term "present
radial diameter", as used herein, means the radial diameter of the
inflatable balloon 105 and/or frame 120.sup.b measured for
performing the comparison to the initial radial diameter.
Therefore, the indication of the radial diameter can comprise a
change in the radial diameter over a plurality of measurements.
According to some embodiments, the at least one diameter sensor can
comprise, as described below: at least one flex sensor; at least
one radially translatable member and a linear displacement sensor;
and/or a strain gauge.
[0426] According to some embodiments, at least one flex sensor 170
is provided, the at least one flex sensor 170 coupled to at least
one strut of the frame 120.sup.b. According to some embodiments, at
least a pair of flex sensors 170 are provided, a first of the pair
of flex sensors 170 coupled to a first strut of the frame 120.sup.b
and a second of the pair of flex sensor 170 coupled to a second
strut of the frame 120.sup.b, the first and second struts
intersecting each other. As described above, control unit 111.sup.b
can monitor the output of the at least one flex sensor 170 to
determine how much the at least one flex sensor 170 has been
flexed. From this information, the control unit 111.sup.b can
determine the opening angle of the at least one strut and can
further determine the radial diameter of the frame 120.sup.b when
expanded, as described above.
[0427] According to some embodiments, at least one radially
translatable member is provided, juxtaposed with an outer surface
240 of the balloon 105. The at least one radially translatable
member can comprise one or more sutures, strings, wires and/or
other flexible, inelastic members configured to have sufficient
rigidity such that the members do not bend, buckle, or stretch or
compress axially when a proximal or distal force is applied thereto
during normal use.
[0428] FIG. 18A shows the balloon 105 in an inflated state, and
further shows a radially translatable member 250 comprising a loop
shaped balloon portion 252 and a connection portion 254. For ease
of illustration and explanation, prosthetic valve 114.sup.b is not
shown in FIG. 18A, but would be positioned around the balloon 105.
The balloon portion 252 surrounds the outer surface 240 of the
balloon 105 and the connection portion 254 extends from the balloon
portion 252 and is coupled to an input of a linear displacement
sensor 260, shown in FIG. 18B. An output of the linear displacement
sensor 260 is in communication with control unit 111.sup.b. The
coupling of connection portion 254 to linear displacement sensor
does not have to be direct. According to some embodiments,
connection portion 254 is connected to a cable 256, cable 256 being
connected to the input of linear displacement sensor 260. As shown,
cable 256 can be coupled to the linear displacement sensor 260.
[0429] As shown in FIG. 18B, the linear displacement sensor 260 can
be implemented using a linear variable differential transformer
(LVDT) sensor, which can comprise a transformer core 262 within a
tube 264, as known to those skilled in the art. The tube can
support the coils (not shown) of the LVDT. Cable 256, or connection
portion 254, can be coupled to the core 262 or the tube 264, to
generate relative motion between core 262 and tube 264. Core 262
can further be in electrical communication with control unit
111.sup.b (not shown). Alternatively, or additionally, the linear
displacement sensor 260 can be implemented using a potentiometer,
as known to those skilled in the art.
[0430] The linear displacement sensor 260 can comprise dedicated
circuitry for the operation thereof and/or to determine the amount
of relative motion applied thereto. Alternatively, or additionally,
the control unit 111.sup.b can operate the linear displacement
sensor 260 and/or to determine the amount of relative motion
applied thereto. The connection portion 254 can be inserted through
an aperture at an end of cable 256. The linear displacement sensor
260 can be positioned within the inflation fluid system 200, within
the handle 110.sup.b or within any other suitable location.
[0431] FIG. 19 shows the balloon 105 in an inflated state, where
the balloon portion 252 of the radially translatable member 250
surrounds the outer surface 240 of the balloon 105. For ease of
illustration and explanation, prosthetic valve 114.sup.b is not
shown in FIGS. 19-20, but would be positioned around the balloon
105. The balloon portion 252 can be positioned within a sleeve,
which can be a stand-alone sleeve, such as the illustrated
circumferential sleeve 270. The circumferential sleeve 270 can be
disposed around the outer surface 240 of the balloon 105 and can
attached thereto by gluing, suturing, or other suitable attachment
mechanism. Alternatively, circumferential sleeve 270 can be an
integral part of the outer surface 240 of the balloon 105.
Circumferential sleeve 270 can support the balloon portion 252 so
as to maintain a generally fixed position of the balloon portion
252 in relation to the balloon 105.
[0432] FIG. 20 shows the balloon 105 in an inflated state, with a
radially translatable member 280 juxtaposed with the outer surface
240 of the balloon 105. According to some embodiments, radially
translatable member 280 comprises: a first balloon portion 282; a
second balloon portion 284; and a connection portion 286. Each of
the first balloon portion 282 and the second balloon portion 284
extends from the connection portion 286. As described above, first
balloon portion 282 and/or second balloon portion 284 can be
positioned within a sleeve, such as sleeve 270. The connection
portion 286 can be inserted through the rod 256 (not shown in FIG.
20).
[0433] According to some embodiments, each of the first balloon
portion 282 and the second balloon portion 284 extends in a
respective direction, the direction of extension of the second
balloon portion 284 generally opposing the direction of extension
of the first balloon portion 282. Particularly, when looking
towards nosecone 109, the first balloon portion 282 can extend
radially about the outer surface 240 of the balloon 105 in a
generally clockwise direction and the second balloon portion 284
can extend radially about the outer surface 240 of the balloon 105
in a generally counter-clockwise direction, or vice versa.
[0434] According to some embodiments, each of the first balloon
portion 282 and the second balloon portion 284 exhibits a
respective distal end 288. Each respective distal end 288 can be
secured to the outer surface 240 of the balloon 105, such as by
being glued thereto. According to some embodiments, the connection
portion 286 can be a single element connecting the first balloon
portion 282 to the second balloon portion 284. Alternatively, the
connection portion 286 comprises a pair of elements, each of the
pair of elements connected to a respective one of the first balloon
portion 282 and the second balloon portion 284. As described above
in relation to the connection portion 254 of the radially
translatable member 250, the connection portion 286 can be coupled
to the linear displacement sensor 260.
[0435] As the balloon 105 expands, the radially translatable member
is radially translated by the radial expansion of the balloon and
as a result the respective connection portion is linearly
translated. For example, the expansion of the balloon 105 moves the
balloon portion 252 of the radially translatable member 250
radially and as a result the connection portion 254 is pulled
linearly. In another example, the expansion of the balloon 105
moves the first balloon portion 282 and the second balloon portion
284 of the radially translatable member 280 radially and as a
result the connection portion 286 is pulled linearly.
[0436] Responsive to an output of the linear displacement sensor,
which senses the amount of linear translation experienced by the
connection portion 286, i.e. how much the connection portion 286
was linearly translated, the control unit 111.sup.b can determine
how much the balloon 105 expanded. Particularly, the amount of
linear translation of the connection portion exhibits a
predetermined relationship with the amount of radial translation of
the respective balloon portion/s, thereby the control unit
111.sup.b can determine the distance that the balloon 105 has
radially expanded. Utilizing the determined amount of radial
expansion, the control unit 111.sup.b can then determine how much
the frame 120.sup.b has expanded. The control unit 111.sup.b can
further determine the radial diameter of the frame 120.sup.b.
[0437] The control unit 111.sup.b can then compare the determined
information to predetermined parameters, such as the maximum
expansion allowed and/or the maximum radial diameter allowed. As
described above, the information can be determined responsive to a
linear displacement sensor and/or at least one flex sensor.
Responsive to an outcome of the comparison, the control unit
111.sup.b can then control the pump 230 to adjust the flow of the
inflation fluid 212. According to some embodiments, the control
unit 111.sup.b can control the pump 230 to stop the flow of the
inflation fluid 212 into the balloon 105 when the determined
expansion amount and/or the determined radial diameter has reached
the respective maximum value. Furthermore, the control unit
111.sup.b can control the pump 230 to slow the flow rate of the
inflation fluid 212 as the determined expansion amount and/or the
determined radial diameter approaches the respective maximum
value.
[0438] FIG. 21 shows an example of an imager 290 as part of
delivery assembly 100.sup.b. Imager 290 can be in communication
with the control unit 111.sup.b. According to some embodiments, the
imager 290 can comprise an x-ray imager. The x-ray imager can
comprise a static imager and/or a fluoroscopy imager. According to
some embodiments, imager 290 can image any relevant portion of
valve 114.sup.b. Responsive to the acquired images, control unit
111.sup.b can determine: the amount that the frame 120.sup.b and/or
the balloon 105 has expanded; and/or the radial diameter of the
frame 120.sup.b and/or the balloon 105. As described above, the
radial diameter of the balloon 105 and the expansion amount of the
balloon 105 are each indicative of the radial diameter of the frame
120.sup.b.
[0439] According to some embodiments, the imager 290 can directly
image the frame 120.sup.b, which is typically composed of a
material that exhibits a high radiation absorption coefficient. The
images can be analyzed by control unit 111.sup.b and/or an
additional computer to determine the expansion amount and/or the
radial diameter of the frame 120.sup.b. Alternatively, or
additionally, a plurality of radiopaque markers 292 are deposited
on predetermined locations of the frame 120.sup.b and/or the
balloon 105. For example, a frame can be made of a non-metallic
(e.g., polymeric) material which is not necessarily radiopaque, in
which case radiopaque markers 292 may be added thereto.
[0440] As shown in FIGS. 22A and 22B, the radiopaque markers 292
can be deposited with predetermined spacings therebetween.
According to some embodiments, the radiopaque markers 292 can be
deposited on the outer surface 240 of the balloon 105 and/or within
the interior of the balloon 105. In embodiments where the
radiopaque markers 292 are deposited on the frame 120.sup.b, the
radiopaque markers 292 can be secured to predetermined struts
121.sup.b. Alternatively, or additionally, one or more radiopaque
bands can be positioned to surround the frame 120.sup.b and/or the
balloon 105. Alternatively, or additionally, one or more
predetermined locations of the frame 120.sup.b and/or the balloon
105 can be coated with a radiopaque coating.
[0441] The images received from imager 290 can then be analyzed to
identify the radiopaque markers 292, band/s and/or coatings, and to
determine therefrom the expansion amount and/or the radial diameter
of the frame 120.sup.b and/or the balloon 105. According to some
embodiments, the expansion amount of the frame 120.sup.b and/or the
balloon 105 can be determined by identifying changes in the
distances between adjacent radiopaque markers 292. Particularly, as
the balloon 105 and/or the frame 120.sup.b expands, the distance
between adjacent radiopaque markers 292 increases.
[0442] FIG. 23 shows the balloon 105 in an inflated state, with a
strain gauge 300 juxtaposed with the outer surface 240 of the
balloon 105. According to some embodiments, the strain gauge 300
can be elongated, and can further be disposed circumferentially on
the balloon 105. According to some embodiments, the length of the
elongated strain gauge 300 can be shorter than the circumference of
the outer surface 240. The strain gauge 300 can be in communication
with the control unit 111.sup.b (not shown). The communication can
be accomplished via a retractable communication channel (not
shown), as described above in relation to communication channel
160. According to some embodiments, the operation of the strain
gauge 300 can be performed in cooperation with the control unit
111.sup.b. The strain gauge 300 can be an electronic strain gauge,
i.e. electrical properties thereof change responsive to the strain
applied thereto. Alternatively, or additionally, the strain gauge
300 can be an optical strain gauge, i.e. optical properties thereof
change responsive to the strain applied thereto.
[0443] It is to be noted that strain gauge 300 is shown in FIG. 25
to circumscribe the balloon 150 by way of illustration and not
limitation, and that the length of the strain gauge 300 in the
circumferential direction can be any suitable length, which can be
significantly shorter than the perimeter of the balloon 105, yet
long enough to provide a significant indication of the increase in
diameter of the balloon during inflation (or deflation) thereof,
when juxtaposed over the balloon's external surface in the
circumferential direction. According to some embodiments, the
strain gauge 300 is glued or sutured to the outer surface of the
balloon 105.
[0444] As the balloon 105 is inflated, the output of the strain
gauge 300 changes responsive to the strain applied thereto, i.e.
responsive to the strain applied to the balloon 105. The output of
the strain gauge 300 thus provides an indication of the diameter of
the balloon 105. As described above, the diameter of the balloon
105 provides an indication of the diameter of the frame 120.sup.b.
Additionally, the control unit 111.sup.b can track the changes in
the output of the strain gauge 300 to determine the amount of
inflation/expansion of the balloon 105 and/or the frame 120.sup.b.
Although the above has been described in relation to an embodiment
where the strain gauge 300 is juxtaposed with the balloon 105, this
is not meant to be limiting in any way. According to some
embodiments (not shown), the strain gauge 300 can be disposed on
the frame 120.sup.b and thus the diameter of the frame 120.sup.b
can be measured directly.
[0445] Although the above has been described in relation to an
illustrated embodiment where a single strain gauge 300 is provided,
this is not meant to be limiting in any way, and a plurality of
strain gauges 300 can be provided. In such an embodiment, each
strain gauge 300 is circumferentially disposed on the balloon 105
over a respective circumferential cross-section.
[0446] As described above, responsive to the determined expansion
amount and/or radial diameter of the balloon 105 and/or the frame
120.sup.b, the control unit 111.sup.b can control the pump 230 to
adjust the flow of the inflation fluid 212 into, and/or out of, the
balloon 105. Advantageously, the pump 230 allows the balloon 105 to
be controllably expanded, thereby providing more accurate
deployment of the balloon expandable valve 114.sup.b. The
additional linear displacement sensor 260 and/or the imager 290, in
combination with the control unit 111.sup.b, provide further
accuracy to the deployment of the balloon expandable valve
114.sup.b.
[0447] As described above, the control unit 111.sup.b, in
cooperation with the pressure sensor 238, can monitor the pressure
of the inflation fluid 212, which exhibits a direct relationship to
the radial forces on the surrounding tissue, and control the pump
230 to maintain the pressure within a desired predetermined range.
According to some embodiments, the control unit 111.sup.b can
determined both the pressure and the radial diameter of the balloon
105 and/or the frame 120.sup.b. For example, the control unit
111.sup.b can compare changes in the pressure to changes in the
diameter. If the pressure rises without a similar increase in
diameter, it can be an indication that pressure against the tissue
is increasing while the balloon 105 has reached its maximum (or
near maximum) expandible parameters, and should not be expanded
further as any further. Similarly, if the diameter increases
without an increase in pressure, it can be an indication that the
balloon 105 has not yet reached its maximum expandible parameters
and should thus may be safely expanded further. According to some
embodiments, the control unit 111.sup.b compares a predetermined
function of the difference between the increase in pressure and the
increase in diameter to a predetermined threshold. The
predetermined function can be a derivative of a curve plotted from:
the increase values of the pressure and diameter; and/or the
absolute values thereof. Responsive to an outcome of the
comparison, the control unit 111.sup.b can control the pump 230 to
adjust the flow of the inflation fluid 212, e.g. to cease the flow
of the inflation fluid 212 into the balloon 105.
[0448] It is known from material science that stress-strain curves
describe the relationship between stress and strain, and are
typically obtained by gradually applying a load (i.e., force) to a
material and measuring the deformation caused thereto as a result
of the applied load. Certain materials exhibit a behavior, in which
the strain initially increases in a proportional ratio to the
increase in the stress applied to the material (the linear elastic
region). After a certain critical point (i.e., yield strength), the
stress increase can cause the material to undergo plastic
deformation and/or to suffer failure (e.g., fracture).
[0449] Is it contemplated that arterial and annular tissues (e.g.,
at a native heart valve) can exhibit certain similar behaviors, as
described in stress-strain curves. For example, upon the initial
application of a radial expanding force (i.e., stress) to the
tissue, and more specifically to the annulus, the annular diameter
can increase in a proportional ratio to the increase in the radial
force applied thereto (an elastic region). After reaching a certain
critical diameter, the tissue is expanded or stretched beyond its
physiological limit, and therefore increasing the application of
radial forces thereto can cause the tissue to sustain irreversible
plastic deformation and/or suffer critical damage (e.g.,
rupture).
[0450] According to some embodiments, the present invention is able
to produce measurements which are indicative of both the prosthetic
valve's or balloon's expansion diameter and the radial forces
exerted thereby on the surrounding tissue, within the desired
implantation site, such as the site of malfunctioning native valve
within the heart. By simultaneously measuring the valve's or
balloon's expansion diameter and the forces exerted thereby on the
surrounding tissue, it is possible to identify the critical
expansion diameter, in which a diameter larger than the critical
diameter will exert increasing radial forces thereto, which can
result in critical damage to the surrounding tissue.
Advantageously, the present invention enables to identify the
critical diameter, thus enabling to expand the valve to a diameter
optionally equal to or smaller than the critical diameter, in order
to prevent possible tissue damage.
[0451] Although the above has been described in relation to a
balloon configured to expand a prosthetic valve, this is not meant
to be limiting in any way. According to some embodiments, the above
systems can be utilized with an inflatable balloon arranged to
expand any suitable type of stent. According to some embodiments,
the above systems can be utilized with an inflatable balloon
configured to be used without an expandable valve, or other stent,
such as during valvuloplasty procedures, pre-ballooning procedures
and post-ballooning procedures. In such embodiments, the control
unit 111.sup.b can be configured to control the operation of the
pump 230 responsive to the expanded radial diameter of the balloon
105 and/or the pressure of the inflation fluid 212.
[0452] FIG. 24A shows a high level flow chart of a delivery method
1000 for a prosthetic valve, in accordance with some embodiments.
The delivery method 1000 can include a step 1010, where at least
one flex sensor is coupled to at least one of a plurality of
intersecting struts of a prosthetic valve. According to some
embodiments, the at least one flex sensor comprises at least a pair
of flex sensors, each of the pair of flex sensors coupled to a
respective one of a pair of the plurality of struts. The pair of
the plurality of struts can intersect each other.
[0453] The delivery method 1000 can further include a step 1020,
where the prosthetic valve of step 1010 is delivered to a
predetermined anatomical location. According to some embodiments,
the prosthetic valve is delivered through the aorta to a target
implantation site, such as a defective heart valve (e.g., the
native aortic valve). The delivery method 1000 can further include
a step 1030, where the delivered valve of step 1020 is moved
between a radially compressed configuration and a radially expanded
configuration. In the radially compressed configuration, the
delivered valve can be crimped to have a minimal radial diameter.
The radially expanded configuration can include a range of radial
diameters of the delivered valve. Movement between the radially
compressed configuration and the radially expanded configuration
can be performed by linear forces applied to the struts of the
valve and/or by inflating a balloon positioned within a frame of
the delivered valve.
[0454] The delivery method 1000 can further include a step 1040. In
step 1040, responsive to an output of the at least one flex sensor
of step 1010, a signal indicative of the radial diameter of the
valve is generated. According to some embodiments, an opening angle
of one or more struts is measured responsive to the output of the
at least one flex sensor, and the radial diameter of the valve is
determined responsive to the measured opening angle.
[0455] FIG. 24B shows a high level flow chart of a delivery method
1100 for a prosthetic valve, in accordance with some embodiments.
The delivery method 1100 can include a step 1110, where at least
one flex sensor is coupled to at least one of a plurality of
intersecting struts of a prosthetic valve. According to some
embodiments, the at least one flex sensor comprises at least a pair
of flex sensors, each of the pair of flex sensors coupled to a
respective one of a pair of the plurality of struts. The pair of
the plurality of struts can intersect each other.
[0456] The delivery method 1100 can further include a step 1120,
where the prosthetic valve of step 1110 is delivered to a
predetermined anatomical location. According to some embodiments,
the prosthetic valve is delivered in a transfemoral approach,
through the aorta to a target implantation site, such as a
defective heart valve. The delivery method 1100 can further include
a step 1130, where the delivered valve of step 1020 is moved
between a radially compressed configuration and a radially expanded
configuration. In the radially compressed configuration, the
delivered valve can be crimped to have a minimal radial diameter.
The radially expanded configuration can include a range of radial
diameters of the delivered valve.
[0457] Movement between the radially compressed configuration and
the radially expanded configuration can be performed by linear
forces applied to the struts of the valve and/or by inflating a
balloon positioned within a frame of the delivered valve. The
radial expansion of the valve during the movement to the radially
expanded configuration flexes a bending portion of the at least one
flex sensor relative to a non-bending portion of the at least one
flex sensor. Particularly, according to some embodiments, each of
the at least one flex sensor is coupled to the valve such that a
first portion of the respective flex sensor bends as the respective
strut opens outwards during the expansion and a second portion of
the respective flex sensor does not bend when the respective strut
opens.
[0458] According to some embodiments, responsive to an output of
the at least one flex sensor, a signal indicative of the radial
diameter of the valve is generated. According to some embodiments,
an opening angle of one or more struts is measured responsive to
the output of the at least one flex sensor, and the radial diameter
of the valve is determined responsive to the measured opening
angle. The opening angle can be determined responsive to the
determined angle between the bending portion and the non-bending
portion of the at least one flex sensor.
[0459] FIG. 24C shows a high level flow chart of a delivery method
1200 for a prosthetic valve, in accordance with some embodiments.
The delivery method 1200 can include a step 1210, where at least
one flex sensor is coupled to at least one of a plurality of
intersecting struts of a prosthetic valve. According to some
embodiments, the at least one flex sensor comprises at least a pair
of flex sensors, each of the pair of flex sensors coupled to a
respective one of a pair of the plurality of struts. The pair of
the plurality of struts can intersect each other.
[0460] According to some embodiments, at least one communication
channel can be coupled to the at least one flex sensor. The at
least one communication channel can be coupled to an output of the
at least one flex sensor. For example, a flex sensor can comprise
an output composed of a pair of electrical leads, the communication
channel being coupled to the pair of electrical leads. The at least
one communication channel can provide electrical and/or optical
communication between an output of the at least one flex sensor and
a control unit. According to some embodiments, the at least one
communication channel can be detachably coupled to the at least one
flex sensor. According to some embodiments, a plurality of flex
sensors and a plurality of communication channels can be provided,
each of the plurality of communication channels coupled to a
respective one of the plurality of flex sensors.
[0461] The delivery method 1200 can further include a step 1220,
where the prosthetic valve of step 1210 is delivered to a
predetermined anatomical location. According to some embodiments,
the prosthetic valve is delivered through the aorta to a defective
heart valve. The delivery method 1200 can further include a step
1230, where the delivered valve of step 1220 is moved between a
radially compressed configuration and a radially expanded
configuration. In the radially compressed configuration, the
delivered valve can be crimped to have a minimal radial diameter.
The radially expanded configuration can include a range of radial
diameters of the delivered valve. Movement between the radially
compressed configuration and the radially expanded configuration
can be performed by linear forces applied to the struts of the
valve and/or by inflating a balloon positioned within a frame of
the delivered valve.
[0462] The delivery method 1200 can further include a step 1240. In
step 1240, subsequent to the valve moving to an expanded
configuration of step 1220, the at least one communication channel
of step 1210 can be retracted from the valve. According to some
embodiments, the at least one communication channel can be detached
from the at least one flex sensor and retracted from the valve.
According to some embodiments, the at least one flex sensor can be
retracted from the valve, with the at least one communication
channel still coupled thereto. According to some embodiments, the
at least one communication channel can be detachable from the at
least one flex sensor upon application of a pull force on the at
least one communication channel responsive to the magnitude of the
pull force being higher than a predetermined threshold
magnitude.
[0463] According to some embodiments, responsive to an output of
the at least one flex sensor, a signal indicative of the radial
diameter of the valve is generated. According to some embodiments,
an opening angle of one or more struts is measured responsive to
the output of the at least one flex sensor, and the radial diameter
of the valve is determined responsive to the measured opening
angle. The opening angle can be determined responsive to the
determined angle between the bending portion and the non-bending
portion of the at least one flex sensor.
[0464] FIG. 25A shows a high level flow chart of a delivery method
2000, in accordance with some embodiments. The delivery method 2000
can include a step 2010, where an inflatable balloon, positioned
within a prosthetic valve is delivered to a predetermined
anatomical location. The prosthetic valve can be delivered through
the aorta to a target implantation site, such as a defective heart
valve.
[0465] According to some embodiments, the delivery method 2000 can
include a step 2020. In step 2020, inflation fluid can be pumped by
a pump into the inflatable balloon of step 2010, thereby inflating
the inflatable balloon. The inflation of the inflatable balloon
expands the expandable prosthetic valve. According to some
embodiments, the pump can be controlled by a control unit.
[0466] According to some embodiments, the delivery method 2000 can
further include a step 2030. In step 2030, the pump can be
controlled to pump at least a portion of the inflation fluid out of
the inflatable balloon. Pumping the inflation fluid out of the
inflatable balloon can be responsive to the control unit of step
2020. According to some embodiments, pumping the inflation fluid of
the inflatable balloon is performed after expansion of the
expandable prosthetic valve.
[0467] According to some embodiments, the delivery method 2000 can
further include a step 2040. In step 2040, an indication of the
radial diameter of the prosthetic valve can be determined. The
indication of the diameter of the prosthetic valve can be
determined responsive to a determination of the radial diameter of
the inflatable balloon. According to some embodiments, the diameter
indication can be determined responsive to at least one radially
expandable member juxtaposed with an outer surface of the
inflatable balloon and coupled to a linear motion sensor, such that
the linear motion sensor measures the amount of radial expansion of
the radially expandable member. According to some embodiments, the
diameter indication can be determined responsive to at least one
strain gauge juxtaposed with an outer surface of the inflatable
balloon. According to some embodiments, the diameter indication can
be determined responsive to at least one flex sensor coupled to at
least one of a plurality of interconnecting struts of the
prosthetic valve. According to some embodiments, the diameter
indication can be determined responsive to images of an imager that
images the prosthetic valve and/or the inflatable balloon. The
imager can image radiopaque markers positioned on a frame of the
prosthetic valve and/or the inflatable balloon. According to some
embodiments, pumping the inflation fluid out of the inflatable
balloon can be responsive to the determination of the radial
diameter of the inflatable balloon and/or the prosthetic valve.
[0468] According to some embodiments, the indication of the
diameter of the prosthetic valve can comprise an indication of the
diameter of the inflatable balloon. For example, the indication of
the diameter of the prosthetic valve can be the measured diameter
of the inflatable balloon. Alternatively, the indication of the
diameter of the prosthetic valve can be another indication of the
radial diameter of the inflatable balloon. For example, the
indication of the radial diameter of the inflatable balloon can
comprise the difference between an initial radial diameter of the
inflatable balloon and the inflated radial diameter of the
inflatable balloon. Therefore, the indication of the radial
diameter of the inflatable balloon can comprise a change in the
radial diameter of the inflatable balloon over a plurality of
measurements. Similarly, the indication of the radial diameter of
the prosthetic valve can comprise a change in the radial diameter
of the prosthetic valve and/or the inflatable balloon over a
plurality of measurements.
[0469] According to some embodiments, the delivery method 2000 can
further include a step 2050. In step 2050, responsive to the
determined radial diameter indication of step 2040, the flow of the
inflation fluid of step 2020 into, and/or out of, the inflatable
balloon is adjusted. The determined radial diameter indication can
be compared to one or more predetermined radial diameter threshold
values, and the flow of the inflation fluid can be adjusted
responsive to an outcome of the comparison.
[0470] FIG. 25B shows a high level flow chart of a delivery method
2100, in accordance with some embodiments. The delivery method 2100
can include a step 2110, where an inflatable balloon, positioned
within a prosthetic valve is delivered to a predetermined
anatomical location. According to some embodiments, the prosthetic
valve is delivered through the aorta to a defective heart
valve.
[0471] According to some embodiments, the delivery method 2100 can
further include a step 2120. In step 2120, inflation fluid can be
pumped by a pump into the inflatable balloon of step 2110, thereby
inflating the inflatable balloon. The inflation of the inflatable
balloon expands the expandable prosthetic valve. According to some
embodiments, the pump can be controlled by a control unit.
[0472] According to some embodiments, the delivery method 2200 can
further include a step 2130. In step 2130, the pressure of the
inflation fluid of step 2120 flowing into the inflatable balloon
can be measured. The pressure can be measured by a pressure sensor
positioned within the inflation fluid flow. The pressure sensor can
be positioned between the pump and the inflatable balloon, and/or
within the inflatable balloon.
[0473] According to some embodiments, the delivery method 2200 can
further include a step 2135. In step 2135, an indication of the
radial diameter of the prosthetic valve, and/or the inflatable
balloon, can be determined, as described above in relation to step
2040 of method 2000.
[0474] According to some embodiments, the delivery method 2100 can
further include a step 2140. In step 2140, responsive to the
measured pressure of step 2130, the flow of the inflation fluid of
step 2120 can be adjusted. According to some embodiments, the
measured pressure of step 2130 can be compared with one or more
predetermined pressure threshold values and the flow of the
inflation fluid can be adjusted responsive to an outcome of the
comparison.
[0475] According to some embodiments, a predetermined function of
the increase in pressure and the increase in diameter can be
determined, and the flow of the inflation fluid can be adjusted
responsive to the predetermined function. The predetermined
function can be compared to a predetermined threshold, and the flow
of the inflation fluid can be adjusted responsive to an outcome of
the comparison. According to some embodiments, the predetermined
function can be a derivative of a curve plotted from: the increase
values of the pressure and diameter; and/or the absolute values
thereof.
[0476] It is appreciated that certain features of the invention,
which are, for clarity, described in the context of separate
embodiments, may also be provided in combination in a single
embodiment. Conversely, various features of the invention, which
are, for brevity, described in the context of a single embodiment,
may also be provided separately or in any suitable sub-combination
or as suitable in any other described embodiment of the invention.
No feature described in the context of an embodiment is to be
considered an essential feature of that embodiment, unless
explicitly specified as such.
[0477] Although the invention is described in conjunction with
specific embodiments thereof, it is evident that numerous
alternatives, modifications and variations that are apparent to
those skilled in the art may exist. It is to be understood that the
invention is not necessarily limited in its application to the
details of construction and the arrangement of the components
and/or methods set forth herein. Other embodiments may be
practiced, and an embodiment may be carried out in various ways.
Accordingly, the invention embraces all such alternatives,
modifications and variations that fall within the scope of the
appended claims.
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